Download Neet PG Microbiology MCQs Question Bank
pathways.Forshorttermcatheters,skincontaminationisthemostlikelymechanismofpathogenesis.Ontheotherhand,forlongtermcatheters,hubcontaminationismore.frequentbecausesuchcathetersoftenhavetobeinterceptedandmanipulated.Skinorganismsmigratefromtheskininsertionsitealongtheexternalsurfaceofcatheter,colonizingthedistalintravasculartipofthecatheter,andultimatelycausingblood-streaminfection.Ontheotherhand,inhubrelatedinfections,organismsareusuallyintroducedintothehubfromthehandsofmedicalpersonnelandtheorganismsmigratealongtheinternalsurfaceofthecatheter,wheretheycancauseabloodstreaminfection.MicrobiologyMostofthemicro-organismsimplicatedinCRIsarisefromtheskinflora.Staphylococciarethemostfrequentlyisolatedpathogens,paricularlycoagulase-negativestaphylococci.Etiologyofcatheterrelatedinfection Microorganism Percentage ?Coagulasenegative 30-40 staphylococci?Staphaureus 5-10 ?Enterococci 4-6 ?Candidaspp. 3-6 ?Pseudomonas 2-5 aeruginosa?Enterobacterspp 1-4 ?Acinetobacterspp. 1-2 ?Serratiaspp. <1 ?Others <1-5
2.Draughtsmancoloniesareseenwith: a)Anthrax b)Pnuemococci c)Pertussis d)Yersenia CorrectAnswer-BPnuemococciDuetoalphahemolysk,coloniesofpneumococcircsemblecoloniesofStr.virtdans.Butonfurtherincubationthecoloniesofpneumococcibecomeflatwithraisededgesandcentralumbonation,sothatconcentricringsareseenonthesurfacewhenviewedfromabove-draughtsmanorCarromcoinappearance.
3.A20yearoldmanpresentedwith abdominalpain,vomitingandbloodydiarrhea,hisstoolsamplegrewEscherichiacoliinpureculture.WhichofthefollowingserotypeofE.coliisthecausativeagentofhemorrhagiccolitis? a)O157:H7 b)O159:H7 c)O107:H7 d)O55:H7 CorrectAnswer-AEnterohemorrhagicE.coliO157:H7istheserotypeofE.colicausinghemorrhagiccolitis. Itisassociatedwiththeingestionofundercookedhamburger,sprouts,unpasteurizedmilkorjuice.EHECproducesashigatoxinandcancausecolitisafteranincubationperiodof3-5days.Ittypicallyproduceswaterydiarrheathatprogresstobloodydiarrheaafterafewhourstofewdays.Fatigue,abdominalpain,nauseaandvomitingareassociatedcomplaints. Mechanismofenterohemorrhagiccolitisappearstobevascularendothelialdamagethatleadstoplateletaggregationandinitiationofthecoagulationcascade.Thisinturn,leadstoischemiaofthe
colonandresultsinhemorrhagiccolitis. Ref:MayoClinicGastroenterologyandHepatologyBoardReviewByStephenHauser,4thEdition,Page197
4.Granulomatosisinfantisepticaiscaused by: a)Pseudomonas b)Chlamydiatrachomatis c)GroupDstreptococci d)Listeria CorrectAnswer-DGranulomatosisinfantisepticaisanintra-uterineinfectionofthenewborncausedbylisteria.Thepredominantfeatureofthisconditionisextensivefocalnecrosisaffectingespeciallytheliverand,lessoften,thelungs.Themortalityrateisveryhigh.Occasionallymeningitismaybeassociatedwithit.Theorganismscanbeisolatedfromtheaffectedareasinthechildandfrequentlyfromthegenitaltractofthemother,whomayormaynotmanifestthedisease. Ref:Harrisonsprinciplesofinternalmedicine,18thedition,Page:1196.
5.Stalactitegrowthingheebrothisdueto thefollowingorganism? a)Y.pestis b)T.palladium c)H.influenzae d)C.diphtheriae CorrectAnswer-ACulturalcharacteristicsofYersiniapestis:1.Whengrowninaflaskofbrothwithoil/gheefloatedontop(gheebroth)acharacteristicgrowthoccurswhichhangsdownintothebrothfromthesurface,resemblingstalactite.2.Onnutrientagar,coloniesaresmall,delicate,transparentdiscs,becomingopaqueoncontinuedincubation.3.Onbloodagarcoloniesaredarkbrownduetoabsorptionoftheheminpigment.4.OnMacConkeyagarcolourlesscoloniesareformed.5.Inbrothaflocculentgrowthoccursatthebottomandalongthesidesofthetube. Ref:TextbookofMicrobiologyAnanthanarayanan,8thedition
6.Milkringtestisdonetodetectwhich organismpresentinmilk? a)Bordetella b)Brucellosis c)Bartonella d)Salmonella CorrectAnswer-Bcorrectanswer-B-->BrucellosisForthedetectionofBrucellaininfectedanimals,pooledmilksamplesmaybetestedforbacillibycultureandforantibodiesbyseveraltechniques.Inthemilkringtest,asampleofwholemilkismixedwellwithadropofstainedbrucellaantigenandincubatedinawaterbathat70degreesfor40-50min.Ifantibodiesarepresentinthemilk,thebacilliareagglutinatedandrisewiththecreamtoformablueringatthetop,leavingthemilkunstained.Ifantibodiesareabsent,nocolourringisformedandthemilkremainsuniformlyblue.AlsoKnow:Bordetellaisdetectedusingthecoughplatemethod,postnasalswab,andthepernasalswabmethod.BartonellabacilliformiscausesOroyafever.Bartonellaquintanacausestrenchfever.Bartonellahenselaecausescatscratchdisease.Salmonellaisdetectedusingawidalreaction.
7.TRUEaboutcorynebacteriumdiphtheriae areall,EXCEPT: a)Hasmetachromaticgranules b)Doesnotinvadedeepertissues c)Toxigenicitydemonstratedbyelek'stest d)Toxinmediatedbychromosomalgene CorrectAnswer-DCorynebacteriaare0.5?1mindiameterandseveralmicrometerslong.Characteristically,theypossessirregularswellingsatoneendthatgivethemthe"club-shaped"appearance.Irregularlydistributedwithintherod(oftennearthepoles)aregranulesstainingdeeplywithanilinedyes(metachromaticgranules)thatgivetherodabeadedappearance.Diphtheriatoxinisabsorbedintothemucousmembranesandcausesdestructionofepitheliumandasuperficialinflammatoryresponse.Ifdisulfidebondsarebroken,themoleculecanbesplitintotwofragments.FragmentB(MW=38,000),whichhasnoindependentactivity,isfunctionallydividedintoareceptordomainandatranslocationdomain.AcidificationofthetranslocationdomainwithinadevelopingendosomeleadstocreationofaproteinchannelthatfacilitatesmovementofFragmentAintothehostcellcytoplasm.ToxinfragmentAinactivatesEF-2bycatalyzingareactionthatyieldsfreenicotinamideplusaninactiveadenosinediphosphate-
ribose-EF-2complex(ADP-ribosylation).Itisassumedthattheabruptarrestofproteinsynthesisisresponsibleforthenecrotizingandneurotoxiceffectsofdiphtheriatoxin.ThetoxigenicityofthecorynebacteriumdiphtheriaeisdemonstratedbyElektest.Ref:BrooksG.F.,CarrollK.C.,ButelJ.S.,MorseS.A.,MietzneronT.A.(2010).Chapter12.AerobicNonspore-FormingGram-PositiveBacilli:Corynebacterium,Listeria,Erysipelothrix,Actinomycetes,&RelatedPathogens.InG.F.Brooks,K.C.Carroll,J.S.Butel,S.A.Morse,T.A.Mietzneron(Eds),Jawetz,Melnick,&Adelberg'sMedicalMicrobiology,25e.
8.RespiratorySyncytialVirus(RSV)causes all,EXCEPT: a)Coryzainkids b)ARDS c)Bronchitis d)Commoncold CorrectAnswer-BRSVinfectionleadstoawidespectrumofrespiratoryillnesses.Ininfantsitcancausepneumonia,bronchiolitis,andtracheobronchitis.Inthisagegroup,illnessbeginsmostfrequentlywithrhinorrhea,low-gradefever,oftenaccompaniedbycoughandwheezing.Inadults,themostcommonsymptomsarecommoncold,withrhinorrhea,sorethroat,andcough.Itcauseseverepneumoniainelderly.Sinusitis,otitismedia,andworseningofchronicobstructiveandreactiveairwaydiseasearealsoassociatedwithRSVinfection.Ref:Harrison'sPrinciplesofInternalMedicine,18thEdition,Chapter186
9.WhoisthefatherofmodernMicrobiology? a)Metchnikoff b)LordLister c)LouisPasteur d)RobertKoch CorrectAnswer-CFatherofModernMicrobiology:LouisPasteur.FatherofMedicalMicrobiology:RobertKoch.FatherofPathology:RudolphVirchow.
10.Microorganismwhichcausespyogenic osteomyelitisis? a)Streptococcus b)Staphaureus c)Corynebacterium d)Neisseriagonorrhoeae CorrectAnswer-BStaphylococcusaureuscauses80?90%ofcasesofacutepyogenicosteomyelitis.Saureushasareceptorforcollagen,whichcontributestoitspathogenicity.Otherorganismsthatcauseosteomyelitisinclude:EscherichiacoliandPseudomonasinintravenousdrugusersandpatientswithurinarytractinfections.HaemophilusinfluenzaeandGroupBStreptococcusinneonates.Salmonellainpatientswithsicklecelldisease.Ref:WyattC.,KempW.L.,MoosP.J.,BurnsD.K.,BrownT.G.(2008).Chapter19.PathologyoftheBonesandJoints.InC.Wyatt,W.L.Kemp,P.J.Moos,D.K.Burns,T.G.Brown(Eds),Pathology:TheBigPicture.
11.TruestatementaboutPneumocystic Jiroveciis: a)OftenassociatedwithCMVinfection b)Usuallydiagnosedbysputumexamination c)Infectionoccursonlyinimmunocompromisedpatients d)AlwaysassociatedwithPneumatocele CorrectAnswer-BPneumocystisJiroveciisusuallydiagnosedbysputumexamination.Ref:MedicalMicrobiologyByJawetz,24thEdition,Pages648-49;WashingtonManualofPulmonaryMedicine,2006,Page104;PneumocystisPneumoniaByWalzer,Cushion,3rdEdition,Page418;Harrison'sPrinciplesofInternalMedicine,16thEdition,Pages1194-95
12.Mycobacteriumtuberculosiswas discoverdby? a)Louispasteur b)Robertkoch c)Lister d)Jener CorrectAnswer-BAns.is'b'i.e.,Robertkoch Scientist AssociatedwithProposedacontagiumvivuin(causeof Fracastorius infectiousdisease)Suggestedthateachdiseaseiscaused VonPlenciz byaseparateagentEarliestdiscoveryofpathogenic AugustinoBassi microorganism Davaineand Observedanthraxbacilliinbloodof Pollender animalFatherofmicrobiology(Alsoseeabove LouisPasteur explanation) RobertKoch FatherofmedicalmicrobiologyDiscoveredM.tuberculosisandVcholeraeIntroducedstainingtechniquesmethodsofobtainingbacteriainpurecultureonsolidmediaSuggestedKoch'spostulate JosephLister FatherofAsepticsurgeryProvedthatsepsiscouldbepreventedby
ProvedthatsepsiscouldbepreventedbyHandhygiene AntonyVan Inventedmicroscope(Fatherof Leeuwenhoek compoundmicroscope)FatherofBacteriology EdwardJenner FatherofImmunology PeytonRous Isolatedviruscausingsarcomainfowl VonBehring& Describedantibody Kitasato
13.Flagellanottrue- a)Locomotion b)Attachment c)Proteininnature d)Antigenic CorrectAnswer-BAns.is'b'i.e.,Attachment
14.Percentageofglutaraldehydeused? a)1% b)2% c)3% d)4% CorrectAnswer-BAns.is'b'i.e.,2%2%Glutaradehyde(cidex)isanaldehydedisinfectantwithabroadspectrumofactionagainstbacteria,fungi,viruses,aswellasspores(slowaction).
15.Innutrientagarconcentrationofagaris- a)1% b)1.5% c)3% d)4% CorrectAnswer-BAns.is'b'i.e.,1.5%NutrientAgarisageneral-purpose,nutrientmediumusedforthecultivationofmicrobessupportingthegrowthofawiderangeofnon-fastidiousorganisms.Nutrientagarispopularbecauseitcangrowavarietyoftypesofbacteriaandfungi,andcontainsmanynutrientsneededforthebacterialgrowth.Nutrientagarismadebyadding1.5%agartothenutrientbroth.0.5%Peptone0.3%beefextract/yeastextract.0.5%NaClDistilledwaterpHisadjustedtoneutral(7.4)at25?C.
16.Naturalmethodofhorizontalgenetransfer amongbacteriaincludes- a)Electroporation b)Transduction c)Transformation d)bandc CorrectAnswer-DAns.is'b'i.e.,Transduction;'c'i.e.,TransformationGenetransferGenetransferreferstotheprocessofgeneticmaterial(e.g.DNA)beingsentandreceivedamongtwoorganisms--->Donorsendsandrecipientreceivesthegeneticmaterial.Therearetwoprocessesofgenetransfer:?1)Horizontalgenetransfer(HGT)orlateralgenetransferHorizontalgenetransferistheprocessbywhichgeneticmaterialispassedbetweentwodifferentorganism,i.e.organismofdifferentspecies.Therecipientisnottheoffspringofdonor.Themostimportantexampleisgenetransferbetweenthebacteria.Theprocessesofhorizontalgenetransferinbacteriaare:- 1. Transduction2. Transformation3. Conjugation 2)VerticalgenetransferVerticalgenetransferistheprocessoftransferringgeneticmaterialtoorganismofsamespecies,i.e.donorrecievesgeneticmaterialfromitsancestor,e.g.itsparentoraspeciesfromwhichitevolved.Therefore,thedonorwillhavethesamegeneralmakeupasthe
parents.Verticalgenetransferis"amixoftwoparents",i.e.whentwoorganismsmate,theirgenesareverticallytransferedtotheirspawn.Thisprocessisnotimportantinbacteria.
17.Whichcellscauserosetteformationwith sheepRBCs- a)Tcells b)NKcells c)Monocytes d)All CorrectAnswer-AAns.is'a.Tcells
18.GenecomponentsofHLAclassIincludes - a)A,B,C b)DR c)DQ d)DP CorrectAnswer-AAns.is'a'i.e.,A,B,C.ClassIHLAcomprisesA,BandCloci.
19.Complementattachestoimmunoglobulin at? a)Aminoterminal b)Fabregion c)Variableregion d)Fcfragment CorrectAnswer-DAns.is'd'i.e.,Fcfragment.Fcfragmentiscomposedofthecarboxyterminal.Itdeterminesthebiologicalactivitysuchascomplementfixation,placentaltransfer,skinfixationandcatabolicrate.CH-2ofIgGandCH,ofIgMbindtoC1qportionofCI.
20.Antigenidiotypeisrelatedto- a)Fcfragment b)Hingeregion c)C-terminal d)N-terminal CorrectAnswer-DAns.is'd'i.e.,N-terminalTheidiotypeisthespecificregionofthefabportion(notFcfragment)ofIgmoleculetowhichantigenbinds.Idiotype(antigenbindingsite)isonvariableregion,whichisataminoterminal(N-terminal).Theaminoacidsequencesofthevariableregionsarenotuniformlyvariablealongtheirlength,butconsistofrelativelyinvariableandsomehighlyvariablezones.ThehigltlyvariableZonesareinvolvedwlththeformationofantigenbindingsites.Thesitesonthehyervariableregionsthatmakeactualcontactwiththeepitopesarecalled"complementaritydeterminingRegions.
21.Idiotypicclassofantibodyisdetermined by- a)Fcregion b)Hingeregion c)Carboxyend d)Aminoend CorrectAnswer-DAns.is'd'i.e.,AminoendTheidiotypeisdefinedasthespecificregionoftheFabportionoftheIgmoleculetowhichantigenbinds.Itisonaminoterminalwhereantigenbindingsiteispresent.
22.Antibodydiversityisdueto- a)Generearrangement b)Genetranslocation c)Antigenicvariation d)aandc CorrectAnswer-DAns.is'a'i.e.,Generearrangement;'c'i.e.,Antigenicvariation
23.Immunoglobulinchangesinvariable region? a)ldiotype b)Isotype c)Allotype d)Epitope CorrectAnswer-AAns.is'a'i.e.,Idiotype
24.Pentavalentimmunoglobinis a)IgA b)IgG c)IgM d)IgE CorrectAnswer-CAns.is'c'i.e.,IgM
25.Maximumhalflife- a)IgG b)IgA c)IgM d)IgE CorrectAnswer-AAns.is'a'i.e.,IgG
26.Whichofthefollowingimmunoglobulinis responsibleforopsonisation- a)IgA b)IgG c)IgM d)none CorrectAnswer-CAns.is'c'i.e.,IgM>'b'i.e.,IgG
27.Activationofclassicalcomplement pathway? a)IgA b)IgG c)IgM d)IgD CorrectAnswer-CAns.is'c'i.e.,IgM
28.TheFcpieceofwhichimmunoglobulin fixesC1 a)IgA b)IgG c)IgM d)candb CorrectAnswer-DAns.is'c'>'b'i.e.,IgM>IgGMakeitveryclearinyourmindthatbothIgMandIgGfixC1."C2ofIgGandC114ofIgMbindtoCIqportionofC1"--------Ananthanarayan"CIqportionofCIisanaggregateof18polypeptidesthatbindstotheFcportionofIgMandigG."---LANGEmicrobiologyHowever,ifyouwillhavetochooseoneoption,IgMisthebestbecauseIgMismoreeffectivethanIgGforcomplementfixation.
29.Antibodyelevatedinparasiticinfection? a)IgA b)IgE c)IgG d)IgM CorrectAnswer-BAns.is'b'i.e.,IgE
30.Papainactsangammaglobulintoform? a)2Fcfragments b)2Fabfragments c)1Fabfragments d)None CorrectAnswer-BAns.is'b'i.e.,2Fabfragments.Papainactsathingeregiontoproduce:?1)OneFefragments2)TwoFabfragments
31.WhichofthefollowingTcellindependent Antigenactsthrough- a)T-cell b)B-cell c)Macrophages d)CD8+Tcells CorrectAnswer-BAns.is'b'i.e.,B-cellsT-cellindependentantigensdirectlystimulatesB-cellswithoutprocessingbyantigenpresentingcells.
32.
Whichpartofbacteriaismostantigenic? a)Proteincoat b)Lipopolysaccharide c)Nucleicacid d)Lipids CorrectAnswer-AAns.isdi.e.,LipidsProteinsaremostimmunogenic,whilelipids&nucleicacidsareleastimmunogenic.Polysaccharides(carbohydrates)arelessimmunogenicthanproteinantigens,butaremoreantigenicthanlipids&nucleicacids.
33.Superantigencauses- a)PolyclonalactivationofT-cells b)StimulationofBcells c)Enhancementofphagocytosis d)Activationofcomplement CorrectAnswer-AAns.is'a'i.e.,PolyclonalactivationofT-cellsSuperantigensarecapableofactivatingupto20%oftheperipheralT-cellpool,whereasconventionalantigensactivate<1in10,000.
34.Prozonephenomenonisseenwith? a)Sameconcentrationofantibodyandantigen b)Inantigenexcesstoantibody c)Antibodyexcesstoantigen d)Hyperimmunereaction CorrectAnswer-C.Ans.is'c'i.e.,Antibodyexcesstoantigen
35.Paulbunnelreactionisatypeof a)Agglutination b)CF c)Precipitation d)Flocculationtest CorrectAnswer-AAns.is'a'i.e.,AgglutinationtestPaulBunnelltestistubeagglutinationtest.
36.Allaretureaboutinnateimmunityexcept ? a)Non-specific b)Firstlineofdefence c)Notaffectedbygeneticaffected d)Includescomplement CorrectAnswer-CAns.is'c'i.e.,Notaffectedbygeneticaffected
37.Whentransferfactorisgivenastreatment resultsin- a)Naturalactiveimmunity b)Artificialactiveimmunity c)Artificialpassiveimmunity d)Adoptiveimmunity CorrectAnswer-DAns.is'd'i.e.,Adoptiveimmunity
38.WhichisfoundinDiGeorge'ssyndrome- a)Tetany b)Eczema c)TotalabsenceofTcells d)AbsentBandTcells CorrectAnswer-AAns.is'a'i.e.,TetanyDigeorgesyndromeDigeorgesyndromeisanexampleofaTcelldeficiencythatresultsfromfailureofdevelopmentofthethirdandfourthpharyngealpouches.*Clinicalfeatures?*Enhancedsusceptibilitytoviral,fungal(mucocutaneouscandidiasis)andbacterialinfections.*Facialabnormalities:Hypertelorism,abnormalears,shortphiltrumandmicrognathia.Hypocalcemictetanyduetofailureofparathyroiddevelopment.Congenitalheartdiseasesegfallot'stetralogy.*Absenceofanormalthymus.*Serumimmunoglobulinconcentrationarefrequentlynormal,butantibodyresponses,particularlyofIgGandIgAisotypes,areusuallyimpaired.*Tcelllevelsarereduced(nottotalabsence).*Bcelllevelsarenormal.
39.Complementformedinliver- a)C2,C4 b)C3,C6,C9 c)C5,C8 d)C1 CorrectAnswer-BAns.isb'i.e.,C3,C6,C9Biosynthesisofcomplementcomponents.Complementcomponentsaresynthesizedinvarioussitesofbody:-i)Intestine-->Clii)Macrophages-->C2,C4iii)Spleen-->C5,C8iv)Liver-->C3,C6,C9
40.Centerofcomplementpathway- a)C3 b)CI c)C5 d)C2 CorrectAnswer-AAns.is'a'i.e.,C3
41.Hereditaryangioneuroticedemaisdueto ? a)DeficiencyofC1inhibitor b)DeficiencyofNADPHoxidase c)DeficiencyofMPO d)Deficiencyofproperdin CorrectAnswer-AAns.is'a'i.e.,DeficiencyofC1inhibitorHereditaryangioneuroticedemaisduetoC1inhibitor(Ciesteraseinhibitor)deficiency.
42.Opsonizationtakesplacethrough- a)C3a b)C3b c)C5a d)C5b CorrectAnswer-BAns.is'b'i.e.,C3b
43.RosetteformationwithsheepRBC's indicatefunctioningof- a)T-cells b)B-cells c)Neutrophils d)Monocytes CorrectAnswer-AAns.is'a'i.e.,T-cellsTcellsbindtosheeperythrocytesformingrosettes(SRBCorErosette)byCD2antigen.
44.Digeorgesyndromeischaracterizedbyall except? a)Congenitalthymichypoplasia b)Abnormaldevelopmentofthirdandfourthpouches c)Hypothyroidism d)Hypocalcemictetany CorrectAnswer-CAns.is'c'i.e.,Hypothyroidism
45.Staphaureuscauses- a)Erythrasma b)Chancroid c)Acnevulgaris d)Bullousimpetigo CorrectAnswer-DAns.is'd'i.e.,BullousimpetigoImpetigoisdividedintotwotypes:?i)Non-bullousimpetigo(Impetigocontagiosum):-Causedbystaphylococcusaureusandstreptococcuspyogenes.ii)Bullousimpetigo:-Causedbystaphylococcusaureus.
46.Glomerulonephritisinstreptococcal infectionisdiagnosedby- a)Bloodculture b)Throatculture c)ASOTitre d)PCR CorrectAnswer-CAns.is'c'i.e.,ASOTitreInrheumaticfeverandglomerulonephritis,retrospectivediagnosisofstreptococcalinfectionmaybeestablishedbydemonstratinghighlevelsofantibodiestostreptococcaltoxins.TheusualtestdoneisantistreptolysinOtitration.ASOtitreshigherthan200unitsareconsideredsignificantandsuggestseitherrecentorrecurrentinfectionwithstreptococci.ASOtitres>200unitsdonotmeanrheumaticfever,itonlyindicatesrecentorrecurrentinfection.
47.Whichgroupofstreptococcusgrowat> 60?C a)A b)B c)C d)D CorrectAnswer-DAns.is'd'i.e.,DAmongstreptococci,enterococcus(groupDstreptococcus)isheatresistant.
48.Pneumococcalvaccineispreparedfrom? a)Cellsurfaceantigen b)Capsularpolysaccharide c)Fromexotoxin d)FromMprotein CorrectAnswer-BAns.is'b'i.e.,CapsularpolysaccharideTherearetwotypesofpneumococcalvaccinesavailable:-1.Polyvalent(23types)polysaccharidevaccineThispolysaccharidevaccinerepresentsthecapsularantigenof23mostprevalentserotypes.Itgives80-90%protectionwhichislong-lasting(5years).Itisnotmeantforgeneraluse,butonlyinpersonsatenhancedriskofpneumococcalinfectionsuchasthosewithabsentordysfunctionalspleen;sicklecelldisease,coeliacdisease;Chronicliverorrenalorlungorcardiacdisease,DM,CSFleaks(meningealdisruption:duraltear)and;immunodeficiencyincludingHIVinfection.Itisnotrecommendedinchildrenundertwoyearsofageandthosewithlymphoreticularmalignanciesandimmunosuppressivetherapy.2.ConjugateVaccineAdifferentpneumococcalvaccinecontainingpneumococcalpolysaccharidecoupled(conjugated)toacarrierprotein(diphtheriatoxoid)hasbeendeveloped.Thevaccinecontainsthecapsularpolysaccharideofsevenmostcommonpneumococcalserotypes,Itcanbegiventochildrenundertheageof2years(butmorethan6weeksold).
49.Meningococcidifferfromgonococciin thatthey? a)Areintra-cellular b)Possessacapsule c)Causefermentationofglucose d)Areoxidasepositive CorrectAnswer-BAns.is'b'i.e.,Possessacapsule
50.Virulenceofgonococciisdueto- a)Pili b)Endotoxin c)Exotoxin d)None CorrectAnswer-AAns.is'a'i.e.,Pili.Majorvirulencefactorforgonococciispill(fimbriae).
51.Meningitiswithrashisseenin- a)Neisseriameningitidis b)H.influenzae c)Strepto.agalactae d)Pneumococcus CorrectAnswer-AAns.is'a'i.e.,Neisseriameningitidis
52.ThevaccineagainstN-meningitidis contains? a)Wholebacteria b)Capsularpolysaccharide c)Somatic'0'antigen d)Noneofthese CorrectAnswer-BAns.is'b'i.e.,CapsularpolysaccharideMeningococcalvaccineMeningococcalvaccinereferstoanyofthevaccinesusedtopreventinfectionbyNeisseriameningitidis.Differentversionsareeffectiveagainstsomeorallofthefollowingtypesofmeningococcus:A,B,C,W-135,andYEffectivevaccinespreparedfrompurifiedGroupA,GroupC,GroupY,andorGroupW-135meningococcalcapsularpolysaccharides.Theimmunityisgroup-specific.Meningococcalvaccinescontainingunconjugatedpurifiedcapsularpolysaccharides(A,C,YandW)havebeenavailablesincethe1970sandarestillusedtoimmunisetravellersandat-riskindividuals.Vaccinescanbeformulatedasbivalent(groupsAandC)ortetravalent(groupsA,C,Y,andW135).Thevaccinesinducegoodimmunityafterasingledoseinolderchildrenandadultsbutareofalittlevalveinchildrenbelow3years.Ittakes10-14daysforimmunitytodevelop.ThereisnoGroupBvaccineavailableatpresent.
53.Daisyheadcoloniesareseenwith- a)Staph.Aureus b)Corynebacteriumdiphtheriae c)Staph.Pyogenes d)Anthrax CorrectAnswer-BAns.is'b'i.e.,CorynebacteriumDiphtheriaeFoursubspeciesarerecognized:C.d.mitis,C.d.intermedius,C.d.gravis,andC.d.belfanti.C.d.GravisColonyonTelluriteBloodAgarishaving2mm,dullgreyishblack,opaquecolonies,daisyhead,brittle,likecoldmargarine.SpecialstainslikeAlbert'sstainandPonder'sstainareusedtodemonstratethemetachromaticgranulesformedinthepolarregions.Thegranulesarecalledpolargranules,BabesErnstgranules,volutinetcdaisy-headcolony.aroundgreyorblackcolonywithanarrowtranslucentscallopedborder,typicallyproducedbyCorynebacteriumdiphtheriaeontelluritebloodagar.
54.The"Stringofpearl"coloniesonNutrient agarisproducedby- a)Klebsiella b)Proteus c)Bacillus d)Salmonella CorrectAnswer-CAns.is'c'i.e.,BacillusStringofpearlreactionStringofpearlreactionisusedtodifferentiateB.anthracisfromB.cereusandotheraerobicspore-formingbacteria.WhenB.anthracisisgrownonasolidmediumcontainingpenicillin,thecellsbecomelarger,sphericalandoccurinchainsonthesurfaceoftheagar,resemblingastringofpearls.
55.Saccharolyticspeciesofclostridia? a)C.tetani b)Cl.cochlearum c)Cl.septicum d)None CorrectAnswer-CAns.is'c'i.e.,Cl.septicumClostridiamaybreakdowncarbohydrateforenergy(saccharolytic)orbreakdownproteinforenergyProteolytic)orboth.Differentclostridiahaveadifferentpattern:-A)BothproteolyticandsaccharolyticPre-dominatingproteolytic-Cl.sporogenes,ClbotulinumA.B.F.,Cl.bifermentans,Cl.histolyticum.Pre-DominatingSaccharolytic-Cl.perfringens,Cl.noyyi,Cl.septicum,Cl.difficile.B)Onlyproteolytic(notsaccharolytic)-Cl.tetaniC)OnlySaccharolytic(notproteolytic)-Cl.botulinumC.D.E.D)Neitherproteolyticnorsaccharolytic-Cl.cochlear
56.Thefollowingstatementsaretrue regardingbotulismexcept- a)Infantbotulismiscausedbyingestionofpreformedtoxin b)ClostridiumbotulinumA,B,CandFcausehumandisease c)Thegeneforbotulinumtoxinisencodedbyabacteriophage d)Clostridiumbarattimaycausebotulism CorrectAnswer-AAns.is'a'i.e.,InfantbotulismiscausedbyingestionofpreformedtoxinInfantbotulismiscausedbyingestionofspores.Sporesareingestedinfood,getestablishedinthegutandthereproducethetoxin."SevenmaintypesofC.botulinum,designatedA-G,produceantigenicallydistincttoxinswithpharmacologicallyidenticalaction.Alltypescancausehumandisease,buttypeA,BandEaremostcommon".(InHarrison&Ananthanarayan,eighttypesofC.botulinumA,B,CI,C2,D,E,F,Ghavebeenmentioned).Toxinproductioninclostridiumbotulinumappearstobedeterminedbypresenceofbacteriophage(atleastintypeC&D)."Clostridiumbutyricumandclostridiumbarattihavealsobeenfoundtoproducetoxin".-Harrison16th/e843-Anystrainproducingtoxinwillobviouslycausebotulism.
57.Botulismismostcommonlydueto- a)Egg b)Milk c)Meat d)Pulses CorrectAnswer-CAns.is'c'i.e.,MeatFollowingnewtypesofbotulismhavebeenaddedin18th/eofHarrison.Adultintestinaltoxemiabotulism:-resultsfromabsorptionoftoxinproducedinsituafterrarelyoccuringintestinalcolonizationwithtoxigenicclostridia..Iatrogenicbotulism:-resultsfrominjectionofbotulismtoxin.
58.Pseudomembranouscolitis,allare trueexcept- a)ToxinAisresponsibleforclinicalmanifestation b)ToxinBisresponsibleforclinicalmanifestation c)Bloodinstoolsisacommonfeature d)Summitlesionsisearlyhistopathologicalfinding CorrectAnswer-CAns.is'c'i.e.,Bloodinstoolsisacommonfeature
59.Shigellaarebedividedintosubgroupon thebasisofabilitytoferment- a)Lactose b)Maltose c)Fructose d)Mannitol CorrectAnswer-DAns.is'd'i.e.,MannitolFermentationofmannitolisofimportanceinclassificationShigellaMannitolfermentingMannitolnonfermentingSh.flexneri(subgroupB)Sh.dysenteriae(subgroupA)Shboydii(subgroupC)Sh.Sonnei(subgroupD)
60.Whichofthefollowingstimulateadenylate cyclasewithG-proteincoupledaction? a)Shigatoxin b)Choleratoxin c)Diphtheriatoxin d)Pseduomonastoxin CorrectAnswer-BAns.is'b'i.e.,Choleratoxin
61.Choleratoxinisdueto- a)Chromosome b)Plasmid c)Phage d)Transposons CorrectAnswer-CAns.is'c'i.e.,Phage.Choleratoxinproductionisdeterminedbyafilamentousphageintegratedwithbacterialchromosome.
62.Psedomonasiswhichtypeofbacteria? a)Anaerobic b)Microaerophilic c)Microaerophilic d)Obligateanaerobe CorrectAnswer-CAns.is'c'i.e.,Microaerophilic
63.WhatisNOTtrueaboutyersiniosis- a)Gram-negativebacillus b)CausedbyYpestis c)Byyersiniaenterocolitica d)Byyersiniapseudotuberculosis CorrectAnswer-BAns.is'b'i.e.,CausedbyyersiniapestisYersiniosisisaninfectiousdiseasecausedbyabacteriumofthegenusYersinia.YersiniaenterocoliticaisaGram-negativebacillus-shapedbacterium,belongingtothefamilyYersiniaceae.Itismotileattemperaturesof22?29?C(72-84?F),butbecomesnonmotileatnormalhumanbodytemperature.[1][2]Y.enterocoliticainfectioncausesthediseaseyersiniosis,whichisananimal-bornediseaseoccurringinhumans,aswellasinawidearrayofanimalssuchascattle,deer,pigs,andbirds.Infectioncausedbyyersiniagenusaredividedinto:-i)Plague:-Itisadeadlyinfectiousdiseasecausedbyyersiniapestis.ii)Yersinosis:-Itischaracterizedbyinfectiousdiarrhea,enteritis,ileitisandoccasionallysepticemia.Itiscausedbyyersiniaenterocolitica(mostcommon)andyersiniapseudotuberculosis.
64.TrueaboutHinfluenza- a)Grownonsheepbloodagar&CO2 b)itisnotcapsulated c)Invasivestrainismostcommon d)Grampositive CorrectAnswer-CAns.is'c'i.e.,InvasivestrainismostcommonInvasivediseaseismorecommonthannon-invasivedisease.H.influenzaedoesnotgrowonbloodagar.Itisgramnegativeandcapsulated.
65.Thumbprintappearanceinculturefilm smearisseen- a)Bacillusanthracis b)Brucella,species c)Bordetellapertussis d)ClostridiumWelchii CorrectAnswer-CAns.is'c'i.e.,BordetellapertussisInculturesmears,thebacilliarearrangedinlooseclumpswithclearspacesinbetweengivingathumbprintappearance.CultureCharacteristicsofBordetellaIncorporationofdiaminefluorideandpenicillin(Lacey'sDFPmedium)makesitmoreselective.Itproducesbisectedpearlormercurydropscolonies.Confluentgrowthispresentwith"aluminiumpaint"appearance.Inculturesmearsthebacilliarearrangedinlooseclumpswithclearspacesinbetweengivingathumbprintappearance.TransportmediausedaremodifiedbyStuart'smediumandMischulo'scharcoalagar.
66.Tuberculintestispositiveifindurationis ? a)>2min b)>5mm c)>7mm d)>10mrn CorrectAnswer-DAns.is'd'i.e.,>10mmThetuberculosisskintestisanothernameforthetuberculintestorPPDtest.ThePPDtestdeterminesifsomeonehasdevelopedanimmuneresponsetothebacteriumthatcausestuberculosis(TB)Atuberculinreactionisclassifiedaspositivebasedonthediameteroftheindurationinconjunctionwithcertainpatient-specificriskfactors.Inahealthypersonwhoseimmunesystemisnormal,indurationgreaterthanorequalto15mmisconsideredapositiveskintest.ProcedureThestandardrecommendedtuberculintestistheMantouxtest,whichisadministeredbyinjectinga0.1mLofliquidcontaining5TU(tuberculinunits)PPD(purifiedproteinderivative)intothetoplayersofskinoftheforearm.Doctorsshouldreadskintests48-72hoursaftertheinjection.Thebasisofthereadingoftheskintestisthepresenceorabsenceandtheamountofinduration(localizedswelling).Anegativetestdoesnotalwaysmeanthatapersonisfreeoftuberculosis.
ApersonwhoreceivedaBCGvaccine(administeredinsomecountriesbutnottheU.S.)againsttuberculosismayalsohaveapositiveskinreactiontotheTBtest.
67.Pigmentproducingatypicalmycobacteria ? a)M.fortutionandM.chelonae b)M.xenopiandMAC c)M.gordonaeandM.szulgai d)M.ulcerans CorrectAnswer-CAns.is'c'i.e.,M.gordonaeandM.szulgaiNon-tubercularmycobacteria(alsocalledatypicalmycobacteria)havebeenclassifiedintofourgroupsbyRunyonbasedonpigmentproductionandrateofgrowth.1)GroupI(photochromogens):-Theseproducepigmentedcolonies(yellow-orange)onlywhenexposedtolight,butnotindark.ExamplesofphotochromogensareM.asiaticum,M.kansasii,M.marinum,andM.simiae.2)GroupII(scotochromogens):-Thesealwaysproducepigmentedcolonies(yellow-orange-red),i.e.indarkaswellasinlight.ScotochromogensareM.flovescens,M.gordonae,M.scrofulaceumandM.szulgi.3)GroupHI(Nonchromogens):-Thesedonotproducepigment.NonchromogensareM.aviumcomplex(MAC),M.haemophilum,M.gastri,M.ulcerans,M.xenopiandM.nonchromogenicum.4)GroupIV(rapidgrowers):-Thisisheterogeneousgroupofmycobacteriacapableofrapidgrowth,coloniesappearingwithin7daysofincubation.Withinthegroup,photochromogenic,scotochromogenicandnonchromogenicspeciesoccur.Chromogenic(pigmentproducing)rapidgrowersaremostlysaprophytic,e.g.M.phleiandM.smegmetis.M.fortuitumandM.
cheloneidonotproduceanypigment.OtherrapidgrowersareM.abscessus,M.vaccae,M.genevense,M.confluentis,andM.intermedium.
68.Fishtankgranulomaisseenin- a)Mfortuitum b)Mkansasi c)Mmarinum d)Mleprosy CorrectAnswer-CAns.is'c'i.e.,M.Marinum'Fishtankgranuloma',alsocalledswimmingpoolgranuloma',iscausedbyM.marinum.
69.Tabesdorsalisisseenin- a)Primarysyphilis b)Secondarysyphilis c)Tertiarysyphilis d)Latentsyphilis CorrectAnswer-CAns.is'c'i.e.,Tertiarysyphilis
70.TrueaboutVDRLtest- a)Non-specific b)Slideflocculationtest c)Bestfollowedfordrugtherapy d)All CorrectAnswer-DAnsis'd'i.e.,All
71.TRUEaboutmycoplasmais- a)Causeslunginfection b)Penicillinisdrugofchoice c)Thickcellwall d)Thalliumacetateinhibitsthegrowth CorrectAnswer-AAns.is'a'i.e.,CauseslunginfectionMycoplasmainfections.Mycoplasmapneumoniaecausesinfectionofupperandlowerrespiratorytract..Highestattackratesin5-20yearsold..Children<5yrsUpperrespiratorysymptoms.Children>5yrs--0.Bronchitisandpneumonia.disease.Aboutotheroptions.Penicillinisnotactiveagainstmycoplasmas..Mycoplasmaslackcellwall.Mycoplasmasareresistanttothalliumacetateinaconcentrationof1:10000
72.Sevensheathedflagellaisseenin- a)Vcholera b)Hpylori c)Psaeroginosa d)Spirochetes CorrectAnswer-BAns.is'b'i.e.,H.pyroliH.pylorihasfivetosevensheathedpolarflagella.VibriocholeraeandPseudomonasaeruginosahavesinglepolarflagellum.Occasionalstrainsofpseudomonasmaycontain2or3flagella.Spirochetes(Treponema)ismotilebyendoflagella.
73.Legionnairediseaseiscausedby? a)Motilegrampositive b)Motilegramnegative c)Non-motilegrampositive d)Non-motilegramnegative CorrectAnswer-BAns.is'b'i.e.,Motilegram-negativeLegionellaisagram-negative,non-capsulatedcoccobacilluswhichismotilebypolarorsubpolarFlagella.Legionellacausesthefollowinginfections:A)PulmonaryinfectionsTherearetwotypesofpulmonaryinfections:-1.PontiacFever:Itisself-limitingflu-likeillnesswithincubationperiod24-48hours.Thereisnopneumonia.2.LegionnairesDisease:Itisatypicalpneumoniawithanincubationperiodof2-l0days.Itischaracterizedbycough.chestpain,hemoptysis,high-gradefever,diarrhoea,confusion,'relativebradycardiaandhyponatremia'.Iftheonsetofsymptomsoccurswithin10daysofdischargefromthehospital,nosocomiallegionnaire'sdiseaseshouldbesuspected.ExtrapulmonaryinfectionsThemostcommonsiteofinfectionistheheart(myocarditis/pericarditis/endocarditis).
74.PatientcamefromNagalandandshows positivetestwithOXKantigen.Diagnosisis? a)Trenchfever b)Scrubtyphus c)Endemictyphus d)Epidemictyphus CorrectAnswer-BAns.is'b'i.e.,ScrubtyphusWeilFelixreaction(DetectOXKantibodies).Thisreactionisanagglutinationtestinwhichseraaretestedforagglutininsto0antigensofcertainnon-motileproteusstrainsOX-19,OX-2andOX-K.Thebasisofthetestisthesharingofanalkali-stablecarbohydrateantigenbysomerickettsiaeandbycertainstrainsofproteus,P.vulgarisOX-19andOX-2andP.mirabilisOX-K.Thetestisusuallydoneasatubeagglutination,thoughrapidslideagglutinationmethodshavebeenemployedforscreening.WeilFelixReaction OX- OX- Disease OX-2 19 K RockyMountain + + ? spottedfever - - ? Rickettsialpox + - _ EpidemictyphusBrill-Zinsser +/- - ? disease
Scrubtyphus - - + Endemictyphus + - ? Trenchfever - ? Qfever -
75.AllaretrueaboutB.Quintanaexcept- a)Causestrenchfever b)Notdetectedbyweilfelixreaction c)Recurrenceiscommon d)Tickisthevector CorrectAnswer-DAns.is'd'i.e.,TickisthevectorTrenchfeverTrenchfever,alsocalled5-dayfeverorquintanfever,iscausedbyBartonellaquintana(Rochalimaeaquintana).Thehumanbodylouce(Pediculushumanscorporis)isthevectorandhumansistheonlyknownreservoir.ClinicalmanifestationsTheincubationperiodis15-25days(range,3-38days).'Classical'trenchfeverpresentsasfebrileillness.Feverisexceedinglyvariable,butcommonlylastsforabout5days.Thefeverisfollowedbyaremissionandarecurrenceafter5days.Theserecurrencesmaybesingleormultipleandupto12recurrencesevery5-6daysarenotuncommon.Othersymptomsandsignsincludeheadache,backandlimbpain,profusesweating,shivering,myalgia,arthralgia,splenomegaly,amaculopapularrashinoccasionalcases,andnuchalrigidityinsomecases.DiagnosisDefinitivediagnosisrequiresisolationofB.quintanabybloodculture.Weil-Felixtestusedfordiagnosisofricketssialinfectionisnegativeintrenchfever.Treatment
Itistreatedwithgentamycinalongwithdoxycycline.
76.Boutonneusefeveriscausedby- a)Rickettsiajaponica b)Rickettsiaconorii c)Rickettsiasibirica d)Rickettsiaaustralis CorrectAnswer-BAns.is'b'i.e.,Rickettsiaconorii TickbornefeverscausedbyRickettsie Organism Fevercaused R.conorii Mediterraneanspottedfever(boutonneusefever)KenyaticktyphusIndianticktyphusSouthAfricanticktyphusIsraelispottedfeverAstrakhanspottedfever R.rickettsii RockymountainspottedfeverR.Afircae Africantick-bitefever(AsimilardiseaseiscausedbyR.parkerinUSandA.trisiteinSouthAmerica) R.japonica Japanesespottedfever(orientalspottedfever) (similardiseaeinNorthAsiaiscausedbyR.sibiricaandR.heilongjiangesis) R.honei FlindersIslandspottedfever R.australis Queenslandticktyphus
77.Whichofthefollowinghasonly1 serotype- a)Cpsittaci b)Cpneumoniae c)Ctrachomatis d)None CorrectAnswer-BAns.is'b'i.e.,CpneumoniaeTherearemanyserovarsofchlamydiae:C.trachomatisTRIC--p.12serotypes}Total15C.trachomatisLGV3serotypesC.psittaci--ManyserotyesC.pneumoniae--10.Onlyoneserotype
78.WhichofthefollowingiscalledasPreisz- Nocardbacillus- a)C.diphtheriae b)C.pseudotuberculosis c)M.tuberculosis d)Mycoplasma CorrectAnswer-BAns.is'b'i.e.,C.pseudotuberculosisBacteriaandtheiralternatenames Bordetella BordetGengoubacillus Clostridiumtetani Nicolaire'sbacillus Corynebacteriumdiphtheriae Klebs-Loeffler'sbacillus Corynebacteriumpseudotuberculosis Preisz-NocardbacillusHaemophilusaegyptius Koch-Weeksbacillus Haemophilusinfluenzae Pfeiffer'sbacillus Klebsiellapneumoniae Friedlander'sbacillus Klebsiellaozaenae Abel'sbacillus KlebsiellaRhinoscleromatis Frisch'sbacillus Mycobacteriumtuberculosis Koch'sbacillus Mycobacteriumintracellulare Battey'sbacillus Mycobacteriumparatuberculosis Johne'sbacillus Mycoplasma Eatonagent Pseudomonaspseudomallei Whitmore'sbacillus
79.Allcausefourniergangreneexcept- a)Staphylococcus b)Streptococcus c)Clostridium d)Bacteroides CorrectAnswer-CAns.is'c'i.e.,ClostridiumFournier'sgangreneisanecrotisingfascitisofgenitalia,usuallyaffectingthescrotumandpenis.TherehavebeenmanytypesofbacteriologicalcultureencounteredinFournier'sgangrene,bothsinglestrainandpolymicrobialculture.Majorityofcasesareduetomixedinfectioncausedbybothaerobicandanaerobicbacteria.Followingarecommoncausativeorganisms:Staphylococcusaureus,streptococcuspyogenes((3-hemolyticstreptococci),enterobacteriaceae(E.coli,klebsiella,proteus),enterococci,pseudomonas,andanaerobeslikebacteroidesandpeptostreptococcus.
80.Necrotizingfascitisiscausedby- a)Staphylococcusaureus b)Betahemolyticstreptococci c)Clostridiumperfringens d)Pneumococcus CorrectAnswer-BAns.is'b'i.e.,BetahemolyticstreptococciThespectrumofinfectionsofthedeepsofttissuesrangesfromlocalizedbacterial,viralandparasiticlesionstorapidlyspreading,tissuedestructiveinfectionssuchasnecrotizingfascitisandmyonecrosis.A)Pyomyositis:-Itiscommonintropics,thereforealsocalledtropicalpyomyositis.Itisalocalizedinfectionofskeletalmuscles.Itiscausedmostcommonlybystaphylococcusaureus.B)NecrotizingfascitisNecrotizingfascitisisaninfectionofthedeeperlayersofskinandsubcutaneoustissues,easilyspreadingacrossthefascialplanewithinthesubcutaneoustissues.Therearetwotypesofnecrotizingfascitis:?i)Type1:-Itisapolymicrobialinfection,i.e.mixedaerobicandanaerobicinfection.Itoccursmostcommonlyaftersurgicalproceduresindiabeticpatientsorinthosewhohaveperipheralvasculardisease.ii)Type2:-Itiscausedmostcommonlybystreptococcuspyogenes(GroupAbetahemolyticstreptococci).C)Clostridialmyonecrosis(Gasgangrene):-Itischaracterizedbyrapidandextensivenecrosisofmuscleaccompaniedbygasformationandsystemictoxicity.ItiscausedbyC.perfringens(mostcommon),C.novyi,C.septicumandC.histolyticum.Itisalsocalled
typeIIInecrotizingfascitis.
81.Whichofthefollowingorganismsdoes notentersthroughabrasionsintheskin- a)Erhusiopathiae b)Ecorrodens c)Chominis d)Cviolaceum CorrectAnswer-CAns.is'c'i.e.,C.hominisBacteriacirculateandmultiplyinblood--->Septicemia.Bacteriacirculateinblood-->Bacteremia.Toxinscirculateinblood-->Toxemia.Pusinblood-->PyemiaEikenellacorrodens(E.corrodens),chromobacteriumviolaceum(C.violaceum)andEikenellacorrodens(E.corrodens)entersthebodythroughskinabrasions.Awidevarietyofmicroorganismsthatresideontheskinandmucousmembranesofthebody,aswellasthosefoundintheenvironment,cancauseskinandsofttissueinfections.Theseorganismsenterthebodythroughbreaksintheskinormucousmembranes,throughwoundsmadebytraumaorbitesorasacomplicationofsurgeryorforeign-bodyimplantation.Theseorganismshavebeenmentionedinfollowingtable: Aerobicand Anaerobicbacteria Aerobic Yeast facultative microorganismsfrom microorganisms unusual,Vspecializedandzoonoticinfections ?Coagulase ? ?Candida Actinobacillus
Actinobacillus negative Peptostreptococcus ? albicans?Candida staphylococci spp. actinomycetemcomitans krusei ? ?Candida Staphylococcus ?Clostridiumspp. ? Aeromonasspp. parapsilosis aureus?Enterococcus ?Eubacterium ? Bacillusanthracis spp. limosum ? ?Bacteroides Streptococcus Bergeyellazoohelcum fragilis viridans ? ? Chromobacterium Corynebacterium ?Prevotellaspp. violaceum spp. ? ?Bacillus ?Porphyromonas ? Eikenellacorrodens cereus?E.coli ?Fusobacterium ? Erysipalothrix ?Serratia ?Veillonellaspp. rhusiopathiae ?Enterobactor ? Francisellatularensis ?Proteus ? Haemophillusspp. ?Morganella ? Kingellakingae ? ? Pasteurellamultocida Pseudomonas Streptobacillus ?Acinetobactor ? moniliformis ? Vibriovulnificus
82.DartingmotilitywhichoccurinV.cholerae, alsofoundin- a)Shigella b)Campylobacterjejuni c)Pneumococcus d)Bacillusanthrax CorrectAnswer-BAns.is'b'i.e.,CampylobacterjejuniDarting(shootingstar)motilityisseeninV.CholeraeGardnerellavaginalisCampylobactor
83.Allaretrueaboutcutaneousanthrax except? a)Extremelypainful b)Thewholeareaiscongestedandedematous c)Centralcrustationwithblackeschar d)Satellitenodulearoundinguinalregion CorrectAnswer-AAns.is'a'i.e.,ExtremelypainfulCutaneousanthraxispainless.
84.Trueaboutvibriocholeraeis- a)Diseasemorecommoninwoman b)Classicalvibrioprotectagainstdevelopmentof0-139Toris milderthanclassical c)El-Torismilderthanclassical d)All CorrectAnswer-CEl-Torismilderthanclassical
85.AppearanceofcowdrytypeAinclusion bodies? a)Granular b)Circumscribed c)Inpolio d)None CorrectAnswer-AAns.is'a'i.e.,GranularIntranuclearinclusionbodieswereclassifiedintotwotypesbycowdry:a)CowdrytypeA:-Theseareofvariablesizeandgranularinappearance,e.g.inherpesvirusandyellowfevervirus.b)CowdrytypeB:-Thesearemorecircumscribedandoftenmultiple,aswithadenovirusandpoliovirus.
86.Whichisenvelopedvirus- a)Denguevirus b)Norwalkvirus c)HepAvirus d)Adenovirus CorrectAnswer-AAns.is'a'i.e.,DenguevirusDenguevirus(amemberofflavivirodae)isanenvelopedvirus.Adenovirus,norwalkvirus(calciviridae)andhepatitisAvirus(Picornaviridae)arenon-envelopedviruses.
87.SmallestDNAvirusis? a)Herpesvirus b)Adenovirus c)Parvovirus d)Poxvirus CorrectAnswer-CAns.is'c'i.e.ParvovirusSmallestvirus(alsosmallestDNAvirus)Parvovirus.Largestvirus(alsolargestDNAvirus)Poxvirus.SmallestRNAvirusPicornavirusLargestRNAvirusParamyxoviridae.
88.Whichofthefollowingisprimarycellline ? a)Chickembryofibroblast b)Helacells c)Verocells d)WI-38 CorrectAnswer-AAns.is'a'i.e.,ChickembryofibroblastChickembryofibroblastisprimarycellculture.
89.Influenzaviruscultureisdoneon? a)Chorioallantoicmembrane b)Allantoiccavity c)Yolksac d)All CorrectAnswer-BAns.isbi.e.,AllantoiccavityInembryonatedeggcultivationforinfluenzavirussiteofinoculationare:-AllontoiccavityoramnioticcavityInoculationsitesinembryonatedeggsChorioallantoicmembrane-4HSV,Poxvirus,Rous-sarcomavirusAmnioticcavity-4Influenzavirus,mumpsvirusAllantoiccavity-Influenzavirus,mumpsvirus,avianadenovirus,newcastlediseasevirusYolksac-->HSV,chlamydia,rickettisia
90.Virusquantificationisdoneby- a)Egginoculation b)Hemadsorption c)Plaqueassay d)Electronmicroscopy CorrectAnswer-CAns.is'c'i.e.,PlaqueassayPlaqueassayandPockassayarequantitativeinfectiveassays.
91.VonMagnusphenomenon- a)Isanormalreplicativecycle b)Virusyieldhaslowhemagglutination c)Virushashighinfectivity d)Virusyieldshashighhemagglutinationtitrebutlowinfectivity CorrectAnswer-DAns.is'd'i.e.virusyieldshashighhemagglutinationtitrebutlowinfectivityAbnormalreplicativecyclesofviruses.Vonmagnusphenomenonwhencellsareinfectedwithahighdoseofinfluenzavirus,thereisdefectiveassemblyduringreplicationandtheproducedvirushashighhemagglutinintitrebutlowinfectivity..AbortiveinfectionDuetodefectivematurationorassembly,eithernoreleaseofvironsoccurortheprogenyofvirusisnoninfectious..DefectivevirusesSomevirusesaregeneticallydefectiveandrequirehelpofsimultaneouslyinfectedhelpervirusforreplication.eg.HDV,Roussarcomavirus.
92.Lysisofbacterialcolonyincultureisseen bywhichvirus- a)Pox b)HSV c)Bacteriophage d)CMV CorrectAnswer-CAns.is'c'i.e.,BacteriophageLysisofbacteriaoccursduetoreplicationofbacteriophageinthebacteria,inlyticcycle.Theprocessoflyticcycleoccursinfollowingsteps:?1)Adsorption(attachment)ofaphagetothesurfaceofasusceptiblebacteriumbyitstail.2)Penetrationofphagenucleicacidintothebacterialcells.3)Synthesisofphagecomponents.4)Assemblyofphagecomponentsintomatureinfectivephageparticles,i.e.maturation.5)Releaseofmatureprogenyphage.
93.Phagetypingcanbedonefor- a)Salmonella b)Streptococcus c)Shigella d)Pseudomonas CorrectAnswer-AAns.is'a'i.e.,SalmonellaPhagetypingisamethodusedfordetectingsinglestrainsofbacteria.Itisusedtotracethesourceofoutbreaksofinfections.Thevirusesthatinfectbacteriaarecalledbacteriophages("phages"forshort)andsomeofthesecanonlyinfectasinglestrainofbacteria.Phagetypingprovidesarapid,accurate,andcheapmethodofinvestigatingSalmonellastrainsforepidemiologicaluse.Salmonellastrainswithinaparticularserovarmaybedifferentiatedintoanumberofphagetypesbytheirpatternofsusceptibilitytolysisbyasetofphageswithdifferentspecificity.Phasetypingisdonefor 1. Salmonella3.Staphaureus2. V.cholerae4.Bacillusanthracis
94.Smallpoxbelongstowhichclassof poxviruses? a)Parapoxvirus b)Capripoxvirus c)Leporipoxvirus d)Orthopoxvirus CorrectAnswer-DAns.is'd'i.e.,Orthopoxvirusi)Entomopoxvirinae:Poxvirusesofinsectswhichdonotinfectvertebrates.Chordopoxvirinaeareclassifiedintosixgeneraorsubgroups-i)Orthopoxvirus:Thesearemammalianpoxvirusesthattendtocausegeneralizedinfectionwithrash.Exmplesarevariola(smallpoxvirus),vaccinia,cowpox,monnkeypox,rabbitpox,buffalopox,camelpox,mousepox.ii)Parapoxvirus:Virusesofungulatesthatmayoccasionallyinfacthuman,eg.Orf(contagiouspustulardermatitis)andparavaccinia(milker'snode,bovinepupularstomatitis).iii)Copripoxvirus:Virusesofgoatandsheeps,eg.sheep-pox,goatpox,lumpyskindisease.iv)Leporipoxvirus:Virusesofofleporids(rabbits,hares,squirrels),e.g.myxomaandfibromas.v)Avipoxvirus:Virusofbirds,eg.fowlpox,turkeypox,pigeonpox,canarypox.vi)Suipoxvirus:Virusofswine,eg.swinepox.
95.Followingvirusisofpoxvirus- a)Variola b)Coxsachie c)ECHO d)HSV CorrectAnswer-AAns.is'a'i.e.,Variola
96.Brick-shapedvirus- a)Chickenpox b)Smallpox c)CMV d)EBV CorrectAnswer-BAns.is'b'i.e.,SmallpoxVariolavirusBelongstoPoxvirusesenvelopedDNA(dsDNA)virus.BrickshapedInstainedpreparationelementarybodiesareseen--)Paschenbodies.Thevariolavirusisthecausativeagentofsmallpox.On8thmay1980whoanouncedglobaleradicationofsmallpox.VacciniavirusItissimilartovariolavirusinproperties.Itisanartificialvirusanddoesnotoccurinnatureassuch.Vacciniavirusisbeingemployedasavectorforthedevelopmentofrecombinantvaccines.Vacciniagenomecanaccomodateabout25000foreignbasepairs,sufficientforintroducingseveralgenes.Manygeneshavebeeninsertedeg-HBV,HIV,rabiesandforpharmacologicallyimportantproductssuchasneuropeptides.Howeveritisnotsuitableasavectorforhumanuseduetoitspathogeniceffects.
97.Apatientwithsorethroathasapositive PaulBunnelltest.Thecausativeorganismis- a)EBV b)Adenovirus c)CMV d)Herpesvirus CorrectAnswer-AAns.is'a'i.e.,EBV.EBVassociatedmalignancies-Burkitt'slymphoma0-Nasopharynagealcarcinoma-Hodgkin'sdisease(mixedcellularitytype)-TonsillarCarcinoma-TCelllymphoma-Thymoma-Gastriccarcinoma-CNSlymphomainAIDSand-AngiocentricnasalNK/Tcellimmunoproliferativelesionstransplantrecipient-Angioimmuno-blasticlymphadenopathy-LeiomyosarcomaOtherassociatednonmalignantconditions-OralhairyleukoplakiainAIDSpatients-Chronicfatiguesyndrome-X-linkedlymphoproliferativesyndrome(Duncan'sdisease)Laboratorydiagnosis
1.Heterophileantibodiestest.Thestandarddiagnosticprocedureinchildrenandyoungadultsisheterophileantibodiestest-Paul-BunnellTest.Atitreof40foldorgreaterisdiagnosticofacuteEBVinfectioninapatientwhohassymptomscompatiblewithinfectiousmononucleosis.Testusuallyremainspositivefor3months.Testisusuallynegativeinchildren<5years,inelderlyorinpatientswithsymptomsnottypicalofinfectiousmononucleosis..Monospottestforheterophileantibodiesismoresensitivethantheclassicalheterphiletest.2.EBVspecificantibodytest.Usedinpatientswholackheterophileantibodies(childrenanti-viralcapsidantigen(anti-VCA)-->mostcommonanti-EBVnuclearantigen(anti-EBNA)anti-earlyantigen(anti-EA)
98.Coxsackievirusis- a)Harpesvirus b)Poxvirus c)Enterovirus d)Myxovirus CorrectAnswer-CAns.is'c'i.e.,Enterovirus
99.Influenzavirushas- a)5segmentsofSSRNA b)8SegmentsofdsDNA c)8segmentsofssDNA d)8segmentsofssRNA CorrectAnswer-DAns.is'd'i.e.,8segmentsofssRNAINFLUENZAVIRUSBelongtoorthomyxoviridae--.Envelope,RNAvirusContainsinglestrandedRNAwhichissegmented--4.8piecesTherearethreeviralsubtypes 1. TypeACausesallpandemicsandmostofthe epidemics 2. TypeBCancauseepidemics3. TypeC-->Causesendemicinfection Threetypesofinfluenzavirusesarecirculatinginworld-->A(HIN1),A(H3N2)andBAnewtypehasbeenrecognized-A(H5NI)Sourceofinfection-->caseorsubclinicalcaseModeoftransmission-->DropletinfectionbyrespiratoryrouteIncubationperiod_________18-72hoursClinicalmanifestations*Mostinfectionsaresubclinical*Fever,headacheandmyalgia*Respiratory-->coughing*ThereisnoviremiaComplications*Pneumonia-->M.C.bystr.pneumoniae*WorseningofCOPD
*WorseningofCOPD*Encephalitis*Reye'sSyndromewithtypeBvirus*GB.Syndrome*GISymptoms(gastricflu)--itypeBvirusLaboratorydiagnosis*mostcommonly,thediagnosisisestablishedbytheuseofrapidviralteststhatdetectviralnucleoproteinorneuraminidase*Bestspecimenisnasopharyngealsecretion.
100.Hemorrhagicfeveriscausedby- a)West-Milefever b)Sandflyfever c)Ebolavirus d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,EbolavirusEbolavirusbelongstohemorrhagicfever(seeaboveexplanation).
101.Whichofthefollowingisnotcommonin India? a)JapaneseBencephalitis b)Lassafever c)KFD d)Dengue CorrectAnswer-BAns.is'b'i.e.,LassafeverSomeArbovirusesknowntobeprevalentinIndia
102.Amplifierhostis- a)PiginJE b)Doginrabies c)ManinJE d)CattleinJE CorrectAnswer-AAns.is'a'i.e.,PigJE
103.TrueabouthepatitisAviurs? a)Causescirrhosis b)HelpsHDVreplication c)Commoncauseofhepatitisinchildren d)Causeschronichepatitis CorrectAnswer-CAns.is'c'i.e.,CommoncauseofhepatitisinchildrenHAVisthemostcommoncauseofhepatitisinchildren.HAVdoesnotcausechronichepatitisorcirrhosis.HBV(noHAV)helpsinHDVreplication.
104.Serologicaltestingofpatientshows HBsAg,IgManti-HBcandHBeAgpostive.Thepatienthase- a)ChronichepatitisBwithlowinfectivity b)AcutehepatitisBwithhighinfectivity c)Chronichepatitiswithhighinfectivity d)Acuteonchronichepatitis CorrectAnswer-BAns.is`b'i.e.,AcutehepatitisBwithhighinfectivity
105.NefgeneinHIVisforuse- a)Enhancingtheexpressionofgenes b)Enhancingviralreplication c)Decreasingviralreplication d)Maturation CorrectAnswer-CAns.is'c'i.e.,DecreasingviralreplicationNonstructuralHIVgenesoTheseare?1)Tat(Trans-activatinggene):Enhancingtheexpressionofallviralgenes.2)Nef(Negativefactorgene):Down-regulatingviralreplication.3)Rev(Regulatorofviralgene):Enhancingexpressionofstructuralproteins.4)Vif(Viralinfectivityfactorgene):Influencinginfectivityofviralparticles.5)Vpu(InHIV-1)andvpx(InHIV-2):Enhancematurationandreleaseofprogenyofvirusfromcells.6)Vpr:Stimulatespromotorregion.7)LTR(Longterminalrepeat)sequence:Containssequenceswhichgivepromotor,enhancerandintegrationsignals.
106.ThechancethatahealthworkergetsHIV fromanaccidentalneedleprickis- a)1% b)10% c)95% d)100% CorrectAnswer-AAns.is'a'i.e.,1% CommonmodesoftransmissionofHIVandtheirrelativerisk Approximate Typesof chanceof exposure infectionper exposure Sexualintercourse:0.1-1.0%anal,vaginal,oralIIBloodandbloodproducts,FactorVII>90%etc.BloodtransfusionIIITissueandorgan50-90%donation,semen,cornea,bonemarrow,kidneyetc.IVInjectionsand0.5-1.0%injuries;sharedneedlesbydrugaddictsInjectionswithunsterileNeedle-stickandotherinjuriesinhealthstaff?Surgicalwounds
SurgicalwoundsVMothertobaby:30%TransplacentalAtbirthAfterbirthBreastmilk
107.Falseaboutp24is a)Seenafter3weeksofinfection b)Cantbeseeninfirstweek c)Cantbedetectedafterseroconversion d)aandc CorrectAnswer-DAns.is'a>c'i.e.,Seenafter3weeksofinfection>CantbedetectedafterseroconversionAntigendetectioninHIVFollowingasinglemassiveinfection,asbybloodtransfusion,thevirusantigensmaybedetectableinbloodafterabouttwoweeks.Themajorcoreantigen,p24istheearliestvirusmarkertoappearinthebloodandistheonetestedfor.IgMantibodiesappearinabout4-6weeks,tobefollowingbyIgGantibodies.Iftheinfectingdoseissmall,asfollowinganeedle-stickinjury,theprocessmaybeconsiderablydelayed.Theappearanceofp24antigenemiaandviremia,followedbyIgMantibodyresponse,coincideswithacuteorseroconversionillness.Afterwards,freep24antigendisappearsfromcirculationandremainsabsentduringthelongasymptomaticphase,toreappearonlywhensevereclinicaldiseasesetsin.Howeverantibody-boundp24antigencontinuestobedemonstrable,afterdissociation.Thep24antigencaptureassay(ELISA)whichusesanti-p24antibodyasthesolidphasecanbeusedforthis.Thetestispositiveinabout30%ofHIVinfectedpersons.Withpriordissociationofantigen-antibodycomplex,thepositivityrateincreasestoabout50%.Thetestismostusefulinpersonsrecentlyexposedtoriskof
infection,inwhomtheantibodytestisnegative.NowcomingtothequestionOptionb&darestraight-forward.p24antigenisdetectedbyELISA(enzymeimmuno-assayorenzymelinkedimmuno-assay)andisnotdetectableinfirstweekaftertheinfection.Option'a'incorrectbecausethoughthep24antigencanbedetectedafter2weeksofinfection:"Thep24antigentestcandetectthep24antigenonaverage10-14daysafterinfectionwithHIV"."Followingasinglemassiveinfection,thevirusantigensmaybedetectableinbloodafterabouttwoweeks".Option'c'ispartlycorrectandpartlyincorrectbecause:-i)Freep24antigenisnotdetectableafterseroconversion.However,in30-50%ofinfectedpersons,antibody-boundp24antigencanbedetectedafteritsdissociationfromantibody.
108.Whichofthefollowingisaprotista- a)Algae b)Fungi c)Protozoa d)Bacteria CorrectAnswer-CAns.is'c'i.e.,Protozoa
109.Trueabouttrematodes a)Twohostrequired b)Segmented c)Anuspresent d)Bodycavitypresent CorrectAnswer-AAns.is'a'i.e.,TwohostrequiredMedicallyimportantmemberoftheclasstrematodabelongtosubclassDigenea,astheyaredigenetic,i.e.requiretwohosts.Thedefinitivehostinwhichtheypassthesexualoradultstagearemammals,humansoranimals,andtheintermediatehostsinwhichtheypasstheirasexualorlarvalstagesarefreshwatermolluscsorsnails.Trematodesareunsegmented,andhavenoanusandbodycavity.
110.Operculatedeggsareseenin- a)Nematodes b)Cestodes c)Trematodes d)Protozoa CorrectAnswer-CAns.is'c'i.e.,TrematodesOperculatedeggshasalittlecaplikestructure(operculum)attheend.Theoperculumpopsopenwhenthenextstageisreadytoemerge.Thenematodes(flukes)layoperculatedeggs.Anexceptionisschistosomeegg,whicharenotoperculated.
111.Amoebicliverabscesscanbediagnosed bydemonstrating- a)Cystsinthesterilepus b)Trophozoitesinthepus c)Cystsintheintestine d)Trophozoitesinthefeces CorrectAnswer-BAns.is'b'i.e.,Trophozoitesinthepus
112.HowmanypairsofflagelladoesGiardia lambliapossess- a)One b)Two c)Three d)Four CorrectAnswer-DAns.is'd'i.e.,Four
113.Acaseofgiardiasispresentswith- a)Nauseaandvomiting b)Abdominalpain c)Steatorrheaandflatulence d)Alloftheabove CorrectAnswer-DAns.is'd'i.e.,AlloftheaboveGiardiasis*Diseasemanifestationsofgiardiasisrangefromasymptomaticcarriagetofulminantdiarrheaandmalabsorption.*Mostinfectedpersonsareasymptomatic*ThemechanismsbywhichGiardiacausesalterationinsmallbowelfunctionarelargelyunknown.Althoughtrophozoitesadheretotheepithelium,theydonotcauseinvasiveorlocallydestructivealterations.*Inmostcasesthemorphologyofthebowelisunalteredbutinfewcases;inchronicallyinfectedsymptomaticpatients;thehistopathologicfinding(flattenedvilli)andtheclinicalmanifestationsresemblethoseoftropicalsprueandglutensensitiveenteropathy.Incubationperiod-Ito3weeks*Clinicalmanifestations*Diarrhea*Nausea*Abdominalpain*Vomiting*Bloating*Flatus*Extraintestinal-urticaria,anterioruveitis,arthritis.*Fever,thepresenceofbloodormucusinthestoolssuggestadifferentdiagnosisasalltheseareabsentingiardiasis.
114.Malarialparasitewasdiscoveredby- a)Ronaldross b)Paulmuller c)Laveran d)Pampania CorrectAnswer-CAns.is'c'i.e.,Laveran.Thespecificcausativeagentofmalariawasdiscoveredintheredbloodcellsofapatientin1880byAlophonseLaveran,aFrencharmysurgeoninAlgeria.Remember.Romanowskydevelopedamethodofstainingmalariaparasitesinbloodfilms.
115.Inmalaria,sexualcycleis- a)Sporozoitetogametocytes b)GametocytestoSporozoite c)Occursinhuman d)Responsibleforrelapse CorrectAnswer-BAns.is'b'i.e.,GametocytestosporozoiteLIFECYCLEOFPLASMODIUMPlasmodiumpassesitslifecycleintwodifferenthosts? 1. Human(intermediatehost)2. Femaleanaphelinemosquito(Definitivehost) Humancycle.Humancyclestartswiththeintroductionofsporozoitesbythebiteofaninfectedanaphelinemosquito..Itcomprisesthefollowingstages.1)Pre-erythrocyticschizogony-Occursinsidetheparenchymacellsoftheliver.-Duringthisphasetheparasitesarenotfoundintheperipheralblood(bloodissterile).-Thelibratedmerozoitesarecalledcryptozoites.-MicromerozoitesenterthecirculationandstartErythrocyticschizogony,whilemacromerozoitesre-enterthelivercellsandstartexoerythrocyticycle(exoerythrocyticcycledoesnotoccurinPfalciparum).-Durationofpre-erythrocyticschizogonyP.vivax-->8daysP.malariae--f15daysP.falciparum-->6daysP.ovale--
>9days2)Erythrocyticschizogony-ParasiteresidesinsidetheRBCs.-Passesthroughthestagesoftrophozoite,Schizontandmerozoite.-Theparasiticmultiplicationduringtheerythrocyticphaseisresponsibleforbringingonaclinicalattackofmalaria.-DurationP.vivax,P.ovale,P.falciparum-->48hrsP.malariae-->72hours3)GametogonyAftererythrocyticschizogony,someofthemerozoitesdevelopintogametocytes.Theindividualwhoharboursthegametocytesisknownasacarrier.4)ExoerythrocyticschizogonySomeofmerozoites,afterpre-erythrocyticschizogony,reinfectliverparenchymacellstostartexoerythrocyticschizogony.Merozoitesliberatedfromexo-erythrocyticschizogonyarecalledphanerozoites.ItisabsentinP.falciparum.Itisresponsiblefortherelapse.MosquitocycleSexualcycleoccursinfemaleAnopheles.Gametocytesaretransferredtotheinsect.Gametocytesdevelopintosporozoitesaftercompletesexualcycle.Sporozoitesareinfectivetoman.
116.Inmalaria,pre-erythrocyticschizogony occursin- a)Lung b)Liver c)Spleen d)Kidney CorrectAnswer-BAns.is'b'i.e.,Liver
117.Whichformofthemalarialparasiteis presentinsalivaofaninfectivemosquito- a)Ringform b)Schizont c)Gametocyte d)Sporozoite CorrectAnswer-DAns.is'd'i.e.,Sporozoite.Sporozoitesareinfectivetoman.Humaninfectionbeginswhenafemaleanophelinemosquitoinoculatesplasmodialsporozoitesfromitssalivaryglandduringabloodmeal.
118.Whichtypeofmalariaisassociatedwith renalfailure- a)Falciparum b)Vivax c)Malariae d)Ovale CorrectAnswer-AAns.is'a'i.e.,FalciparumNephroticsyndrome-->quartamalaria(P.malariae)Acutetubularnecrosis(renalfailure)malignanttertianmalariaorperniciousmalaria(causedbyPfalciparum).
119.Malariacausingnephroticsyndrome- a)P.vivax b)P.falciparum c)P.malariae d)P.ovale CorrectAnswer-CAns.is'c'i.e.,P-malariaeNephroticsyndromeisseeninQuartanmalarialnephropathy,causedbyrepeatedorchronicinfectionwithP.malariae.
120.JSBstainisusedforwhichparasite? a)Malaria b)Filaria c)Kalaazar d)Sleepingsickness CorrectAnswer-AAns.is'a'i.e.,MalariaJSB(Jaswant-Singh-Bhattacherji)stainisafairlyrapidstainingmethodforthedetectionofmalarialparasites.Thisstainissuperiortothefield'sstainbecausetheparasitesstainclearerandboththickandthinsmearscanbestained.However,preparationsfadequiterapidlyandthisstainis,therefore,notrecommendedwhenpermanentslidesaredesired.StainsusedforstainingmalarialsmearsAnumberofRomanowskystainsareusedforexampleField's,Giemsa's,Wright'sandLeishman's.Forthicksmear,thestainsusedare:(i)Field'sor(ii)Giemsa's.Forthinsmear,thestainsusedare(i)Giemsa'sor(ii)Leishman's.JSBstainisusedforboththickandthinsmears,andisthestandardmethodusedbylaboratoriesundertheNationalMalariaEradicationProgrammeinIndia.
121.Cylindricalhelminthsare- a)Tapeworms b)Flukes c)Roundworms d)Cestodes CorrectAnswer-CAns.is'c'i.e.,RoundwormsHelminths(metazoa)aredividedinto? 1. Nemathelminthes:Thesearecylindrical(round),thereforearecalled round-worms(nematodes). 2. Platyhelminthes:Theseareflatanddividedinto: Cestodes(tapeworms):ThesearesegmentedTrematodes(flukes):Theseareleaf-likeCylindricalHelminthsNematodes(round-worms)FlatsegmentedhelminthsCestodes(tape-worms)Flat,leaf-likehelminthsTrematodes(flukes)
122.Consumptionofuncookedporkislikely tocausewhichofthefollowinghelminthicdisease- a)Taeniasaginata b)Taeniasolium c)Trichuristrichiura d)Noneofthese CorrectAnswer-BAns.is'b'i.e.,TaeniasoliumHumansacquireintestinaltapeworminfectionbyingestingundercookedporkcontainingcysticerci.Modeofinfectionoftapeworms 1. T.saginata-->Undercookedbeefcontainscysticercusbovis.2. Tsolium-->Undercookedporkcontainingcysticercuscellulosae& rarelybyingestionofegg(autoinfection.) 3. Trichuris-trichiuracausedbyingestionofinfectiveeggviafaeco- oralroutefromcontaminatedsoil. 4. Hydatidcystiscausedbyingestionofinfectiouseggviafaeco-oral routefromcontaminatedsoil.
123.Katayamafeveriscausedby- a)F.hepatica b)C.sinensis c)S.haematobium d)A.lumbricoides CorrectAnswer-CAns.is'c'i.e.,S.haematobiumKatayamafever(AcuteSchistosomiasis)occursinaboutamonthafterinfecionwithS.japonicumandS.mansoniandrarelywithS.haematobium.
124.Childhavingperianalprurituswith followingeggsisdueto- a)E.vermicularis b)Ascaris c)Ancylostomaduodenale d)Sstercoralis CorrectAnswer-AAns.is'a'i.e.,E.vermicularisClinicalfeaturesofthreadwormInfections*Mostpinworminfectionsareasymptomatic.*Perianalpruritisisthecardinalsymptom.Theitching,isworseatnightanddisturbessleep.*Heavyinfectionscancauseabdominalpainandweightloss.*Nocturnalenuresis*Vulvovaginitis*Pelvicandperitonealgranulomasrare*Appendicitis*Salpingitis
125.Wucheriabancrofti,trueis- a)Unsheathed b)Tailtipfreefromnuclei c)Non-periodic d)All CorrectAnswer-BAns.is'b'i.e.,TailtipfreefromnucleiW.bancroftiissheathedandperiodicwithtailtipfreefromnuclei.
126.Calabarswellingisproducedby? a)Onchocercavolvulus b)Loaloa c)Burgiamalayi d)Wuchereriabancrofti CorrectAnswer-BAns.is'b'i.e.,Loa-LoaLoiasisLoiasisiscausedbyL.Loa(theAfricaneyeworm)Habitatofadultwormsissubcutaneousconnectivetissueofman;ofteninthesub-conjuctivaltissueoftheeye.Thewormpassesitslifecycleintwohosts:1)Man&2)Chrysops(Mangoordeerflies)C/FsAsymptomaticmicrofilaremia,Calabar(fugitive)swelling-subcutaneousswelling,Nephropathy,Encephalopathy(rare),CardiomyopathyCalabarswellingisduetohypersensitivityreactiontotheadultworm.
127.Riverblindnessiscausedby- a)Onchocerca b)Loaloa c)Ascaris d)B.malayi CorrectAnswer-AAns.is'a'i.e.,OnchocercaOnchocerciasisisalsoknownasRiverblindnessandRoblesdisease.
128.Cutaneouslarvamigransisdueto? a)Ankylostomabraziliensis b)W.bancrofti c)B.Malayi d)D.medinensis CorrectAnswer-AAns.is'a'i.e.,AnkylostomabrazilienseLarvamigrans.Certainnematodelarvaeonenteringintounnaturalhost(e.g.man)maynotbeabletocompletetheirjourneythroughthehost'stissuesforlocalizationintheirnormalabode..Twodifferenttypesofconditionsareproduced. 1. Enteringbyskinpenetration-Cutaneouslarvamigrans orcreepingeruption 2. Enteringviaoralroute-Viscerallarvamigrans.
129.Schistosomiasisistransmittedby? a)Cyclops b)Fish c)Snaile d)Cattle CorrectAnswer-CAns.is'c'i.e.,SnailsIntermediatehostforschistosomasp.issnail.
130.Cercariaeareinfectiveformof- a)S.hematobium b)P.westermanii c)F.hepatica d)T.solium CorrectAnswer-AAns.is'a'i.e.,S.hematobiumCercariaofSchistosomahematobiumistheinfectiveform.
131.Whichofthefollowingistoxicto parasite- a)Peroxidase b)Interferon c)IL-2 d)IL-6 CorrectAnswer-AAns.is'a'i.e.,PeroxidaseNeutrophilsandmonocytescontainaperoxidase(myeloperoxidase),thathasbeenimplicatedinantiparasiticactivity.However,monocyteslosethisenzymewhentheymatureintomacrophages.Eosinophilsalsocontainperoxidasethatdiffersfrommyeloperoxidaseofneutrophils.However,likemyeloperoxidase,eosinophilperoxidasecombineswithH20,andahalidetoformanantiparasitesystem.ParasiteEggsize1)Fasciolagigantica190X100m2)Echinostomailiocanum100X70m3)Gastrodiscoideshominis150X70-100m4)Opisthorcisviverni<30X15m
132.Hangingdropmethodisusedfor- a)T.trichomonas b)Plasmodium c)Toxoplasma d)Cryptosporidium CorrectAnswer-AAns.is'a'i.e.,T.trichomonasHangingdropmethodisusedforexaminingmotilityofmicro-organisms.Motilityoftrichomonasvaginalismayalsobeobservedbythismethod.
133.Whichofthefollowingistrueabout malaria? a)Gametocyteharbourersarecarrier b)Allstageinerythrocyticschizogonyseeninfalciparuminfection inperipheralblood c)SchizontsofvivaxdonotcompletelyfilltheRBC d)Allthecorrect CorrectAnswer-AAns.is'a'i.e.,Gametocyteharbourersarecarrier*Theindividualwhoharboursthegametocytesisknownasacarrier.*Onlyringform(youngtrophozoites)andgametocytesareseeninperipheralblood.*SchizontofP.vivaxalmostcompletelyfillsanenlargedR.B.C.
134.Whichofthefollowingisonlyyeast? a)Candida b)Mucor c)Rhizopus d)Cryptococcus CorrectAnswer-DAns.isdi.e.,Cryptococcus
135.Thefunguswithseptatehyphaeand dichotomousbranchingis- a)Aspergillus b)Penicillium c)Mucor d)Rhizopus CorrectAnswer-AAns.is'a'i.e.,AspergillusSeptatehyphaewithdichotomousbranchingintotwoequaldivisonsataregularangleof45?aretypicalofAspergillus.Mucorandrhizopusarenon-septate(aseptate)andpenicilliumhasnohyphae(Itisyeastlikefungus).
136.Acuteangledseptatehyphaeareseenin ? a)Aspergillus b)Mucor c)Penicillium d)Candida CorrectAnswer-AAns.is'a'i.e.,AspergillusSeptatehyphaewithacutebranchingischaracteristicofaspergillus.
137.Aseptatehyphaeisnotseenin- a)Rhizopus b)Mucor c)Aspergillus d)None CorrectAnswer-CAns.is'c'i.e.,AspergillusNon-septate(aseptate)hyphae-->Rhizopus,mucor.Septatehyphae-->Aspergillus.
138.Whichofthefollowingisfalseregarding dimorphicfungi- a)Occursintwogrowthforms b)Cancausesystemicinfection c)Cryptococcusisanexample d)Coccidioidesisanexample CorrectAnswer-CAns.is'c'i.e.,CryptococcusisanexampleDimorphicfungiFungithathavetwogrowthforms,suchasmold(filaments)andayeast,whichdevelopunderdifferentgrowthconditions..Inhosttissuesorculturesat37?Ctheyoccurasyeasts,whileinthesoilandinculturesat22"Ctheyappearasmoulds..Mostfungicausingsystemicinfectionsaredimorphicfungi.Note-Candidaalbicansisadimorphicfungus,whileotherspeciesofcandidaarenotdimorphic.
139.Trichophytonspecieswhichiszoophilic ? a)T.tonsurans b)T.violaceum c)T.schoenleinii d)T.mentagrophytes CorrectAnswer-DAns.is'd'i.e.T.mentagrophytesZoophilicdermatophytesarethespecieswhichprimarilyinfectanimalsandoccasionallytransmittedtohumans.ZoophilicspeciesoftrichophytonareT.montegrophytesandTverrucosum.OtherzoophilicspeciesofdermatophytesisM.canis.
140.Tineacrurisiscausedby- a)Epidermophyton b)Trichophyton c)Microsporum d)aandb CorrectAnswer-DAns.is'a'i.e.,Epidermophyton;'b'i.e.,Trichophyton
141.Hairperforationtestispositivein infectionwith? a)Trichophyton b)Microsporum c)Epidermophyton d)Alloftheabove CorrectAnswer-AAns.is'a'i.e.,TrichophytonHairperforationtest.Thehairperforationtestconsistsofinoculatingcoloniesofanorganismintoadishcontainingasmallamountofwater,afewdropsofyeastextractsolutionandsomehumanhair.Thedishisincubatedat300Candafter7days,someofthehairaretakenandarekeptonaslidewithacoverslipandareobservedunderamicroscope.Thetestisconsideredpositiveifthehairhasdeep,narrowwedgeshapedperforationinit..Hairperforationtestisdonetodistinguishbetweenisolatesofdermatophytes,particularlytrichophytonmentagrophytesanditsvariants.
142.Colorofgranulesinmycetomacaused byActinomadurapelletierrii- a)Black b)Yellow c)Red d)Brown CorrectAnswer-CAns.is'c'i.e.,RedColoutofGrainsinMycetomasofVariousEtiology WhitetoYellow BrowntoBlack Red 1)Nocardia 1)Madurella 1)Actinomadura asteroides mycetomi pelletierrii 2)Nocardia 2)Madurella brasilliensis grisea 3)Actinomadura 3)Phialophora madurae jeanselmei 4)Streptomyces somaliensis5)Allescheriaboydii
143.Aspergilluscausesallexcept? a)Bronchopulmonaryallergy b)Otomycosis c)Dermatophytosis d)Allergicsinusitis CorrectAnswer-CAns.is'c'i.e.,Dermatophytosis
144.Valleyfeverordesertrheumatismis causedby? a)Sporothrix b)Cladosporium c)Phialophora d)None CorrectAnswer-DAns.is'None'Ans.is'None'Coccidioidomycosis,commonlyknownascocci,Valleyfever,aswellasCaliforniafever,desertrheumatism,andSanJoaquinValleyfever,isamammalianfungaldiseasecausedbyCoccidioidesimmitisorCoccidioidesposadasii.ThescientificnameforValleyfeveris"coccidioidomycosis,"andit'salsosometimescalled"SanJoaquinValleyfever"or"desertrheumatism."Theterm"Valleyfever"usuallyreferstoCoccidioidesinfectioninthelungs,buttheinfectioncanspreadtootherpartsofthebodyinseverecases.
145.Aplantprickcanproduce sporotrichosis.Allaretruestatementsaboutsporotrichosisexcept- a)Isachronicmycoticdiseasethattypicallyinvolvesskin, subcutaneoustissueandregionallymphatics b)Mostcasesareacquiredviacutaneousinoculation c)Enlargedlymphnodesextendingcentripetallyasabeaded chainareacharacteristicfinding d)Itisanoccupationaldiseaseofbutchers,doctors CorrectAnswer-DAns.is'd'i.e.,Itisanoccupationaldiseaseofbutchers,doctors*Sporotrichosisiscausedbythethermallydimorphicfungussporothrixschenckii.*BecauseS.schenckiinaturallyfoundinsoil,hay,sphagnummoss,andplants,itusuallyaffectsfarmers,gardeners,andagriculturalworkers.*Thisfungaldiseaseusuallyaffectstheskinalthoughrareformscanaffectthelungs,joints,bonesandCNS.*Fungusentersthroughsmallcutsandabrasionsintheskintocausetheinfection.*Becauserosescanspreadthedisease,itisoneofafewdiseasesreferredtoasrose-thornorrosegardener'sdisease.Formsandsymptomsofsporotrichosis:1)Cutaneous(skin)sporotrichosis*Thisisthemostcommonformofthisdisease.*Symptomsofthisformincludesnodularlesionsorbumpsintheskin,atthepointofentryandalsoalonglymphnodesandvessels.*Thelesionstartsoffassmallandpainless,noduleandrangesin
*Thelesionstartsoffassmallandpainless,noduleandrangesincolourfrompinktopurple.*Leftuntreated,thelesionbecomeslargerandlookssimilartoaboilandmorelesionswillappear,untilachroniculcerdevelops.*Usuallycutaneoussporotrichosislesionsoccursinthefinger,handandarm.2)Pulmonarysporotrichosis*ThisrareformofthediseaseoccurwhenS.schenckiisporesareinhaled.*Symptomsincludeproductivecough,nodules,cavitationsandfibrosisoflungs;andhilarlymphnodeenlargement.*Patientswiththisformofsporotrichosisaresusceptibletodevelopingtuberculosisandpneumonia.3)Disseminatedsporotrichosis*Whentheinfectionspreadsfromtheprimarysitetosecondarysitesinthebody,thediseasedevelopsintoarareandcriticalformcalleddisseminatedsporotrichosis.*Theinfectioncanspreadtojointsandbones(calledosteoarticularsporotrichosis)aswellastheCNSandbrain(sporotrichosismeningitis).
146.Whichisfalseaboutpenicilliummarefi- a)Blackcolonies b)Dimorphicfungi c)AmphotericinBusedfortreatment d)Causesfulminantinfectionsinimmunocompromisedpatients CorrectAnswer-AAns.is'a'i.e.,BlackcoloniesPenicilliummarneffeiPenicilliummorneffeicauseseriousdisseminateddiseasewithcharacteristicpapularskinlesioninAIDSPatientsinSouth-EastAsia.Thefungusisdimorphic,formingyeast-likecellsthatareoftenintracellular,resemblinghistoplasmosis,ininfectedtissues.Theyeastphase(37?C)displayscoloniesthatarewhitetotan,softanddry.Themostdistinguishingcharacteristicofmouldphase(at25?C)istheearlypresenceofredpigmentthatdiffusesintoagar.Thecoloniesstartaspinkish-yellowandevolveintoabluish-greencolorinthecenterwithawhiteperiphery.Itisassociatedwithbamboorat(Rhizomyssinensis)andhasbeenisolatedfromtheirburrowsandinternalorgans.TreatmentisamphotericinB,followedbyintracoazoletopreventrelapse.
147.Neurotropicfungusis/are- a)Cryptococcusneoformans b)Histoplasmosis c)Trichophyton d)aandb CorrectAnswer-DAns.is'a'i.e.,Cryptococcusneoformans;'b'i.e.,HistoplasmosisFungiinfectingthebrainareCryptococcusneoformansBlastomycesdermatitidisCoccidioidesimmitisAspergillussp.Candidasp.SporothrixschenckiiHistoplasmacapsulatum
148.Pneumocystiscariniiisdiagnosedby- a)Sputumexaminationfortrophozoitesandcystunder microscope b)Culture c)Positiveserology d)Growthonartificialmedia CorrectAnswer-AAns.is'a'i.e.,Sputumexaminationfortrophozoitesandcystundermicroscope
149.Bacteriashowingantigenicvariation? a)Yersinia b)Bordetella c)Brucella d)Borrelia CorrectAnswer-DAns.is'd'i.e.,BorreliaBacteriashowingantigenicvariationare:?i)Neisseria(Meningococci,Gonococci)ii)Streptococcussppiii)Mycoplasmaiv)Borreliaburgdorferi
150.BioterroismgroupAagent a)Qfever b)Typhusfever c)Brucella d)Antrax CorrectAnswer-DAns.is'd'i.e.,Antrax
151.Whichofthefollowingbelongsto category-Bofbioterrorism- a)Cholera b)Anthrox c)Plague d)Botulism CorrectAnswer-AAns.is'a'i.e.,Cholera
152.Mostcommonmodeoftransmissionof nosocomialinfectionis- a)Handcontact b)Dropletinfection c)Bloodandbloodproducts d)Contaminatedwater CorrectAnswer-AAns.is'a'i.e.,HandcontactModesoftransmissionofnosocomialinfectionsTherearefollowingtypesofmodesoftransmissionofhospital-acquiredinfections.1)Contacttransmission*Itisthemostcommonandmostpreventablemeansoftransmission.Itisdividedintotwotypes-.0Directcontact:Itinvolvescontactofbodysurfacetobodysurfacewithaphysicaltransferofmicroorganisms.Handcontactismostcommonmodeoftransmission.ii)Indirectcontact:Itinvolvesbodysurfacecontactwithacontaminatedintermediateobject.2)Droplettransmission*Itoccurswhendropletcontainingmicroorganismsfromaninfectedpersonarepropelledthroughtheair(e.g.coughing,sneezing)andlandonthemouth,eyesornoseofanotherperson.3)Airbornetransmission*Itresultswhenadropletcontainingmicroorganismsevaporatesandremainssuspendedinairforalongtime(thisshouldnotbeconfusedwithdropletinfection,inwhichtransmissionisimmediateanddropletsdonotremainssuspendedintheair).
*Airbornetransmissionalsooccursbydustparticlescontainingmicroorganism.4)Vehicletransmission*Itreferstotransmissionofinfectionbycontaminateditemssuchasfood,water,medications,devicesandequipment.
153.Mostcommonorganisminvolvedin nosocomialinfection- a)Staphaureus b)E.coli c)Legionella d)Streppneumonia CorrectAnswer-AAns.is'a'i.e.,Staphaureus.UTIisthemostcommontypeofnosocomialinfection..MostcommoncauseofUTI--->Ecoli.MostcommoncauseofUTIinICU---->Candida.Overallstaphaureusisaleadingcauseofnosocomialinfection..Staphaureusisthemostcommoncauseofsurgicalwoundinfection-.Mostcommoncauseofprimarybacteremia-->Coagulasenegativestaphylococcus.
154.Mostcommonorganismcausing ventilatorassociatedpneumonia- a)Legionella b)Pneumococcus c)Pseudomonas d)Coagulasenegativestaphylococcus CorrectAnswer-CAns.is'c'i.e.,PseudomonasStaphylococcusaureusandPseudomonasaeruginosacausemostofthecasesofventilatorassociatedpneumonia(VAP).OthercommonorganismscausingVAPareenterococcusfaecium,Acinetobacterbaumonnii,enterobacterspeciesandklebsiellapneumoniae.Mnemonic:ESKAPE(Enterococcus,staphylococcus,klebsiella,Acinetobacter,Pseudomonas,enterobacter).Assinglemostcommonorganism,pseudomonasisthecausativeagent? -Pseudomonas --> 21% aeruginosa-Staphylococcus --> 20% aureus-Enterobacterspecies --> 9% -Klebsiella --> 8% pneumoniae-Acinetobacter --> 6%
155.Indonovanosis- a)Pseudolymphadenopathy b)Penicillinisusedfortreatment c)Painfululcer d)Suppurativelymphadenopathy CorrectAnswer-AAns.is`a'i.e.,PseudolymphadenopathyDonovanosisCausedbyCalymmatobacteriumgranulomatis.C.granulomatisis?GramnegativeEncapsulatedNonmotileIntracellularItsharesmanymorphologicandserologiccharacteristic(antigenic)and>99%homologyatthenucleotidelevelwithKlebsiella.ClinicalmanifestationsIP1-4weeksBeginsasoneormoresubcutaneousnodulesthaterodethroughskintoproduceclean,granulomatous,sharplydefined,usuallypainlesslesions.Thegenitaliaareinvolvedin90%ofcases.Genitalswelling,particularlyoflabia,iscommon.Indonovanosis,heaped-upgranulomatoustissuemayfollowandviasubcutaneousextensiontoinguinalareamayform"pseudo-buboes";however,theabsenceoftruelymphadenopathyisthehallmarkofthisinfection.ComplicationsPseudoelephantiasis,phimosisandparaphimosis.
Diagnosis:ThepreferreddiagnosticmethodinvolvesdemonstrationoftypicalintracellularDonovanbodieswithinlargemononuclearcellsvisualizedinsmearspreparedfromlesionsorbiopsyspecimens.Stainusediswright-GiemsaTreatment:Azithromycin(DOC)Doxycycline(2'dchoice)Chloramphenicol
156.Anadolescentmaledevelopedvomiting anddiarrhea1hourafterhavingfoodfromarestaurant.Themostlikelypathogenis? a)Clostridiumperfringens b)Vibrioparahaemolyticus c)Staphylococcusaureus d)Salmonella CorrectAnswer-CAns.is'c'i.e.,Staphylococcusaureus.Amongthegivenoptions,onlystaphylococcuscancausegasteroenteritiswithin6hours.
157.18yearsoldgirlpresentswithwatery diarrhea.Mostlikelycausativeagent- a)Rotavirus b)V.cholerae c)Salmonella d)Shigella CorrectAnswer-BAns.is'b'i.e.,V.choleraeAmongstthegivenoptionsRotavirusandV.choleraecausewaterydiarrhea.Acutewaterydiarrhainchildrenisusuallybacterialinorigin,mostcommonlyduetoenterotoxigenicE.coli(ETEC).Vcholeraeisalsoacommoncause.Rotavirusisthemostcommoncauseofdiarrheaininfantandchildren(thepatientinquestionisadult).
158.Thepredominantcolonicbacteriaare- a)Largelyaerobic b)Largelyanaerobic c)Bacteroides d)Staphylococci CorrectAnswer-BAns.is'b'i.e.,Largelyanaerobic*Intheadultnormalcolon,theresidentbacterialfloraaremostly(96-99percent)anaerobes:*Anaerobicstreptococci(Peptostreptococci)-Clostridia*Anaerobiclactobacilli(bifidobacteria)-Bacteroides*1-4percentareaerobes:*Enterococci*Pseudomonas*Coliforms*Lactobacilli*ProteusRemember*Induodenumandupperileum,predominantorganismsare-->Lactobacilliandenterococci.*Inlowerileumandcecum-->Floraresemblethefecalflora.
159.Memorycellsare: September2004 a)Basophils b)Eosinophils c)Lymphocytes d)Neutrophils CorrectAnswer-CAns.Ci.e.Lymphocytes
160.ComplementFixationtestis: September2005 a)VIDAL b)Coombstest c)Wassermannreaction d)VDRL CorrectAnswer-CAns.C:WassermannreactionThecomplementfixationtest(CFT)wasextensivelyusedinsyphilisserologyafterbeingintroducedbyWassermanin1906.However,thereisnowatrendtoreplacetheCFTwiththesimpleflocculationtests.AlthoughCFTisconsideredtobearelativelysimpletest,itisaveryexactingprocedurebecause5variablesareinvolved.Inessencethetestconsistsoftwoantigen-antibodyreactions,oneofwhichistheindicatorsystem.Thefirstreaction,betweenaknownvirusantigenandaspecificantibodytakesplaceinthepresenceofapredeterminedamountofcomplement.Thecomplementisremovedor"fixed"bytheantigen-antibodycomplex.Thesecondantigen-antibodyreactionconsistsofreactingsheepRBCwithhaemolysin.Whenthisindicatorsystemisaddedtothereactants,thesensitizedRBCswillonlylyseinthepresenceoffreecomplement.TheantigensusedforCFTtendtobegroupantigensratherthantype-specificantigens.InorderfortheCFTtobesetupcorrectly,theoptimalconcentrationofhaemolyticserum,complement,andantigenshouldbedeterminedbytitration.TheWassermanntestisnolongerinuse.
161.ConfirmatorytestforSyphilisis: September2010March2013 a)VDRL b)Rapidplasmareagintest c)FT-ABS d)Alloftheabove CorrectAnswer-CAns.C:FT-ABST.pallidumcannotbegrowninvitroDiagnostictestsforsyphilis:Testsincludeserologictestsforsyphilis(STS),whichconsistofscreening(reaginic)andconfirmatory(treponemal)tests,anddarkfieldmicroscopy.Reaginictestsuselipidantigens(cardiolipinfrombovinehearts)todetectreagin(humanantibodiesthatbindtolipids).TheVenerealDiseaseResearchLaboratory(VDRL)andrapidplasmareagin(RPR)testsaresensitive,simple,andinexpensivereaginicteststhatareusedforscreeningbutarenotspecificforsyphilis.Resultsmaybepresentedqualitatively(e.g.,reactive,weaklyreactive,borderline,ornonreactive)andquantitativelyastiters(e.g.,positiveat1:16dilution).Manydisordersotherthantreponemalinfections(e.g.,SLE,antiphospholipidantibodysyndromes)canproduceapositive(biologicallyfalse-positive)reagintestresult.CSFreaginictestsarereasonablysensitiveforearlydiseasebutlesssoforlateneurosyphilis.CSFreagintestscanbeusedtodiagnoseneurosyphilisortomonitorresponsetotreatmentbymeasuringantibodytiters.Treponemaltestsdetectantitreponemalantibodiesqualitatively
andareveryspecificforsyphilis.Theyincludethefollowing:Fluorescenttreponemalantibodyabsorption(FTA-ABS)testMicrohemagglutinationassayforantibodiestoT.pallidum(MHA-TP)T.pallidumhemagglutinationassay(TPHA)
162.Nosocomialinfectionismostcommonly causedby:March2004 a)Gramnegativebacilli b)Grampositivebacilli c)Gramnegativecocci d)Mycoplasma CorrectAnswer-AAns.Ai.e.Gramnegativebacilli
163.Entericfeveriscausedby: September2005 a)Salmonellatyphi b)SalmonellaparatyphiA c)SalmonellaparatyphiB d)Alloftheabove CorrectAnswer-DAns.D:AlloftheaboveTyphoidfeveriscausedbySalmonellatyphi.ParatyphoidfeveriscausedbySalmonellaparatyphiA,BandC.Thetermentericfeverencompassesbothtyphoidandparatyphoidfevers.
164.Ghon'sfocusreflects: September2005 a)Miliarytuberculosis b)Primarycomplex c)Tuberculouslymphadenitis d)Postprimarytuberculosis CorrectAnswer-BAns.B:PrimarycomplexOnlyaverysmallpercentofMycobacteriumtuberculosis(MTB)infectionsresultindisease,andevenasmallerpercentageofMTBinfectionsprogresstoanadvancedstage.Thebacilliisengulfedbyalveolarmacrophagesmultiplyandgiverisetoasubpleuralfocusoftuberculouspneumonia,commonlylocatedinthelowerlobeorthelowerpartoftheupperlobe.ThisisknownasGhonfocus.TheGhonfocustogetherwiththeenlargedhilarlymphnodeconstitutestheprimarycomplex.SmallmetastaticfocicontaininglownumbersofMTBmayalsocalcify.However,inmanycasesthesefociwillcontainviableorganisms.ThesefociarereferredtoSimonfoci.TheSimonfociarealsovisibleuponchestX-rayandareoftenthesiteofdiseasereactivation.
165.Diphtheriatoxin'smechanismofaction is:September2009 a)Inhibitingglucosesynthesis b)Inhibitingproteinsynthesis c)Promotingacetylcholinerelease d)AlteringcyclicGMPlevels CorrectAnswer-BAns.B:InhibitingproteinsynthesisThediphtheriatoxincausesthedeatheucaryoticcellsandtissuesbyinhibitionofproteinsynthesisinthecells.Althoughthetoxinisresponsibleforthelethalsymptomsofthedisease,thevirulenceofC.diphtheriaecannotbeattributedtotoxigenicityalone,sinceadistinctinvasivephaseapparentlyprecedestoxigenesis.
166.Mostseriouscomplicationofmeaslesis: September2008 a)Croup b)Meningo-encephalitis c)Otitismedia d)Pneumonia CorrectAnswer-BAns.B:Meningo-encephalitisMeaslesisahighlycommunicableacutedisease.Itisalsoknownasrubeolaandismarkedbyprodromalfever,cough,coryza,conjunctivitis,andpathognomonicenanthem(i.e.,Koplikspots),followedbyanerythematousmaculopapularrashonthethirdtoseventhday.Infectionconferslife-longimmunity.Ageneralizedimmunosuppressionthatfollowsacutemeaslesfrequentlypredisposespatientstobacterialotitismediaandbronchopneumonia.Inapproximately0.1%ofcases,measlescausesacutemeningo-encephalitis,whichisthemostseriouscomplication.Subacutesclerosingpanencephalitis(SSPE)isararechronicdegenerativediseasethatoccursseveralyearsaftermeaslesinfection.
167.
PromastigoteformofLeishmaniaisfoundinwhichpartofsandfly:March2005 a)Lymphnode b)GIT c)Spleen d)Bonemarrow CorrectAnswer-BAns.B:GIT
168.Forphagetyping,howmanyphagesof staphylococcusaureusareused? a)12 b)15 c)20 d)23 CorrectAnswer-DAns.is'Di.e.,23Bacteriophagetypingofstaphylococcusisbasedonthesusceptibilityofcoccitobacteriophages.Thisiscarriedoutbypatternmethodwhereasetof23standardtypingphagesofS.aureusisusedtotypestaphylococcalisolatesanddistinguishthemfromoneanotherbytheirpatternsofsusceptibilitytolysis.Thephage-typeofastrainisknownbythedesignationofthephagesthatlyseit.Forexample,ifastrainislysedbyphages83A,84and85,itiscalledtype83A/84/85.
169.MostcommonbiotypeofS.aureus causinghumaninfection? a)A b)B c)C d)D CorrectAnswer-AAns.is'a'i.e.,AStaphylococcusaureushasbeenclassifiedintosixbiotypes:A,B,C,D,EandF.MosthumanpathogenicstrainsbelongtobiotypeA.
170.Mostcommonpoxvirusinfectionin humanis? a)Smallpox b)Monkeypox c)Cowpox d)Mulluscumcontagiosum CorrectAnswer-DAns.is'd'i.e.,MulluscumcontagiosumAmongthegivenoptions,smallpox(variola)virusandmolluscumcontagiosumaffecthumanastheirprimaryhost.Smallpoxhasbeeneradicated.Molluscumcontagiosumisacommonskininfection.
171.HHV-6causes? a)Erythemainfectiosum b)Kaposisarcoma c)Roseolainfantum d)Herpangina CorrectAnswer-CAns.is'c'i.e.,Roseolainfantum
172.Phenylalaninedeaminasetestispositive in? a)Salmonella b)Proteus c)Vibriocholerae d)Helicobacter CorrectAnswer-BAns.is'b'i.e.,ProteusThedistinctivecharacterofproteusgenusisdeaminationofphenylalaninetophenylpyruvicacid(PPA+ye)
173.Grampositive,catalasenegativecocci? a)Staphaureus b)Staphepidermidis c)Staphsaprophyticus d)Pneumococcus CorrectAnswer-DAns.is'd'i.e.,Pneumococcus
174.R-factorinbacteriaistransferedby? a)Transduction b)Transformation c)Conjugation d)Verticaltransmission CorrectAnswer-CAns.is'c'i.e.,ConjugationConjugationBacterialconjugationisthetransferofgeneticmaterialbetweenbacteriathroughdirectcelltocellcontactorthroughabridge-likeconnectionbetweentwocells.Conjugationisprocesswherebyadonor(male)bacteriummakesphysicalcontactwitharecipient(female)bacterium.Donorstatusisdeterminedbythepresenceofplasmid.Thisplasmidcodesforspecializedfimbria(sexpilus)andforselftransfer.Sexpilus(conjugationtube)helpsintransferofgeneticmaterialfrommalebacteriumtofemalebacterium.Theplasmidisknownastransferfactor(sexfactororfertilityfactor).PlasmidmaybeRfactor,whichcodesfortransferrablemultipledrugresistance.TheDNAoftheplasmidreplicatesduringtransfersothateachbacteriumreceivesacopyRecipientbecomesdonorandthedonorretainsitsdonorstatus.
175.Fecesaredisinfectedbestby? a)1%formaldehyde b)5%cresol c)5%phenol d)Isopropylalcohol CorrectAnswer-BAns.is'b'i.e.,5%cresol"Themosteffectivedisinfectantforgeneraluseisacoal-tardisinfectantwithaRideal-Walker(RW)coefficientof10ormoresuchascresol".
176.Stoolspecimenistransportedin? a)Caryblairmedium b)Bloodagar c)SeleniteFbroth d)CompyBAPmedium CorrectAnswer-AAns.is'a'i.e.,CaryblairmediumTransportmediaforstoolspecimenare:? a. Cary-Blairmediumb. Bufferedglycerolsaline c. Stuartmedium Inoculatemediaforroutinestoolcultureare:- a. Bloodagarb. MacConkeyagar c. HektoenentericHE(agar) d. Selectivemediaforcampylobactor:CampyBAP,skirrowe. SeleniteFbrothorGNBroth f. Xylose-lysinedeoxycholateagar(XLDagar) Forspecificsituations,selectivemediaareused:- i. Vibrio:TCBSagarorAlkalinepeptonebroth. ii. Yersinia:Cefsulodin-Irgasan-Novobiosin(CIN)agarorPhosphate BufferedSaline(PBS)broth. iii. E.coli0157:H7:Sarbitol-MacConkeyagar.
177.HEPAfilterisusedtodisinfect? a)Water b)Air c)Culture d)Blood CorrectAnswer-BAns.is'b'i.e.,AirHEPA(High-efficiencyparticulateair)filterisusedtoremovemicroorganismsfromair.HEPAfiltertrapsairborneparticlesandmicrobes.Itcanremove>95%ofallparticlesincludingmicroorganismswithadiameter>0.3p.m.
178.Virusmostsensitivetoinactivationby biocides? a)Adenovirus b)Herpesvirus c)Parvovirus d)Poliovirus CorrectAnswer-BAns.is'b'i.e.,HerpesvirusEnvelopedvirusesaremostsensitivetoinactivationbybiocides.AmongthegivenoptionsonlyHerpesvirusisenvelopedvirus.Adenovirus,parvovirusandpoliovirus(picornavirus)arenon-envelopedviruses.
179.Complementcomponentsare? a)Lipoproteins b)Glycoproteins c)Polysaccharides d)Lipid CorrectAnswer-BAns.is'b'i.e.,GlycoproteinsTheproteinsandglycoprotiensthatconstitutethecomplementsystemaresynthesizedbyhepatocytes"--Internet"Mostofthecomplementglycoproteinsaresynthesizedpredominantlybytheliver,butmacrophagesandmanyothercelltypesarealsosourcesofvariouscomplementcomponents"-Medicalimmunology"Complementcomponentsareglycoproteins"--TextbookofHumanBloodPlasmaProtiens
180.TrueaboutCampylobacterjejuni? a)Obligateaerobe b)Oxidasenegative c)Growsat42?C d)Non-motile CorrectAnswer-CAns.is'C'i.e.,Growsat42?CCampylobacterjejuniMorphologyGramnegativeCommashapedMotilewithasinglepolarflagellumDartingortumblingmotilityNoncapsulatedNonSporingCultureGrowthoccursundermicroaerophilicconditions(5%O2,10%CO2and85%N2).Thermophilic,growingat42?C(Cangrowat37?C,butincubationathighertemperaturessuppressesnormalfecalflora.)BiochemicalreactionsDonotfermentcarbohydrateCatalaseandoxidase-positiveNitratereductionpositive
181.Bestindicatorforsterilizationby autoclaving? a)Bacillussubtilis b)Geobacillus c)Bacilluspumilis d)Clostridium CorrectAnswer-BAns.is'b'i.e.,GeobacillusBiologicalindicatorsBiologicalindicatorsarestandardisedpreparationsofmicroorganismsusedtoassesstheeffectivenessofasterilizationprocess.Theyusuallyconsistofapopulationofbacterialsporesplacedonaninertcarrier,forexampleastripoffilterpaper,aglassslideoraplastictube.Mostcommonly,sporesofBacillusstereothermophilus(Geobacillusstearothermophilus)areused.SporesofBacillussubtilisandBacilluspumilisarealseused.
182.Satellitismisseeninculturesof? a)Hemophilus b)Streptococcus c)Klebsiella d)Proteus CorrectAnswer-AAns.is'a'i.e.,HaemophilusSatellitismThegrowthofHaemophilusinfluenzaeisscantyonbloodagar,asthefactorVisnotfreelyavailable,beingimprisonedinsidetheredbloodcells.Growthis,therefore,betterifthesourceoftheVfactorisalsoprovided.WhenStaphaureusisstreakedacrossaplateofbloodagaronwhichaspecimencontainingH.influenzaehasbeeninoculated,afterovernightincubation,thecoloniesofH.influenzaewillbelargeandwelldevelopedalongsidethestreakofstaphylococcus,andsmallerfurtheraway.Thisphenomenoniscalledsatellitism.Satellitismisduetoahighconcentrationoffactor'V'instaphaureuswhichisreleasedintomediumandisusedbyH.influenzae.
183.Varicellazostervirusbelongstowhich familyofDNAviruses? a)Poxviridae b)Herpesviridae c)Adenoviridae d)Papovaviridae CorrectAnswer-BAns.is`b'i.e.,HerpesviridaeDNAvirusesPoxviridae:-Variola,vaccinia,cowpox,monkeypox,tanapox,molluscumcontagiosumHerpesviridae:-HSV-1,HSV-2,varicella-zoster,EBV,CMV,HTLV-1,RK-virusAdenovirideAdenovirusParvoviridaeParvovirus,Adenosatellovirus,DensovirusPapovaviridaePapillomavirus(HPV),PolyomavirusHepadnaviridaeHepatitis-Bvirus
184.C1esteraseinhibitordeficiencycauses? a)Neisseriainfection b)Hereditaryangioneuroticedema c)Hemolyticdisease d)Hemolyticuremicsyndrome CorrectAnswer-BAns.is'b'i.e.,HereditaryangioneuroticedemaHereditaryangioneuroticedemaisduetoC1inhibitor(CIesteraseinhibitor)deficiency.
185.Runtdiseaseis? a)Graftrejection b)Graftvshostdisease c)Hostvsgraftdisease d)TypeIIIhypersensitivity CorrectAnswer-BAns.is'b'i.e.,Graftvshostdisease
186.Trueabouthydatidcystareall,except? a)Mostcommonsiteisliver b)Calcificationiscommoninlung c)Mayinvolvekidney d)Livercystsaremorecommoninrightlobe CorrectAnswer-BAns.is'b'i.e.,CalcificationiscommoninlungHydatiddiseaseLivercystsThemajorityofhydatidcystsoccurintheliver,causingsymptoms:ChronicabdominaldiscomfortPalpableabdominalmassAllergicreactionsduetocystrupture-skinrash,anaphylacticshock,ordeath.AbscessformationduetosecondrybacterialinfectionLivercystsoccurmorefrequentlyintherightlobe.LungcystSecondmostcommonorgan(afterliver)UsuallyasymptomaticOccasionallymaycausesymptoms.Leastcommonsiteofcalcifiedhydatidcyst.Radiographicsigns 1. Meniscussign2. Water-lilysign,camalotesign3. Risingsunsign,serpentsign4. Emptycystsign
187.Virulencefactorforclostridiumtetani? a)Endotoxin b)Tetanolysin c)Tetanospasmin d)Bacteremia CorrectAnswer-CAns.is'c'i.e.,TetanospasminPathogenicityofCItetaniCl.tetanihaslittleinvasivepropertyandisconfinedtotheprimarysiteoflodgment.Tetanusresultsfromtheactionofthepotentexotoxinitproduces.ToxinsofCItetani1)Tetanolysin(Hemolysin)Notrelevantinthepathogenesisoftetanus.2)Tetanospasmin(neurotoxin)ResponsiblefortetanusItisplasmidcodedInthebrainstemandspinalcorditblocksreleaseoftheinhibitoryneurotransmitterglycineand'yaminobutyricacid(GABA).Itresemblesstrychnineinitseffects,butitactspresynaptically,whilestrychnineactspostsynaptically.oTetanustoxinandbotulinumtoxinresembleeachotherintheiraminoacidsequences.3)Nonspasmogenic,peripherallyactiveneurotoxinItsroleisnotknown
188.Whichmyxovirusdoesnothave hemagglutininandneuraminidasebuthavemembranefusionprotein- a)Measles b)Parainfluenza c)RSV d)Influenza CorrectAnswer-CAns.is'c'i.e.,RSVRSVdoesnotposseshemagglutininorneuraminidase.Theviralenvelopehastwoglycoproteins?i)GproteinBywhichvirusattachestocellsurfaceii)F-protein(Fusionprotein)whichbringaboutfusionbetweenviralandhostcellmembranes.Itisalsoresponsibleforcelltocellfusion,whichleadstocharacteristicsyncytialformation.
189.Whichpriondiseaseaffecthuman? a)Scrapie b)Madcowdisease c)Kuru d)Bovinespongiformencephalopathy CorrectAnswer-CKuruprionInfectionthroughritualisticcannibalism
190.Peritrichousflagellaeareseenin? a)Vibriocholerae b)Proteus c)Campylobacter d)Legionella CorrectAnswer-BAns.is'b'i.e.,Proteus
191.Molluscumcontagiosumvirusbelongs to? a)Poxviruses b)Herpesviruses c)Picornaviruses d)Adenovirus CorrectAnswer-AAns.is'a'i.e.,Poxviruses
192.Trueaboutvibriovulnificus? a)Causesdiarrheacommonly b)Halophilic c)Drugofchoiceispenicillin d)Producesshigatoxin CorrectAnswer-BAns.is'bi.e.,HalophilicV.VulnificusV.vulnificusisahalophilicvibrio.Ithasbeenlinkedtotwodistinctsyndrome.
193.Trueaboutdiphtheriatoxin? a)Heatstable b)ActsthroughcGMP c)Consistsofthreefragments d)Specialaffinityforbrain CorrectAnswer-AAns.is'a'i.e.,Heatstable"Diphtheriatoxinisaheat-stablepolypeptide,composedoftwofragments"-MedicalmicrobiologyDiphtheriatoxinThediphtheriatoxinactsbyinhibitingproteinsynthesis.Itinhibitspolypeptidechainelongationinthepresenceofnicotinamideadininedinucleotide(NAD)byinactivatingelongationfactor,EF-2.Thediphtheriatoxinisaproteinwhichconsistsoftwofragments,AandB.Bothfragmentsarenecessaryforthetoxiceffect: 1. FragmentA-hasenzymaticactivityandinhibitsproteinsynthesisby inhibitingthechainelongationbyinactivatingtheelongationfactor-2(Ef-2) 2. FragmentB-responsibleforbindingthetoxintothecells. Toxinhasspecialaffinityforcertaintissuessuchasmyocardium,adrenalsandnerveendings.Thestrainalmostuniversallyusedfortoxinproductionisthe"Parkwilliams8strain".
194.Howdoeschlamydiadifferfromother usualbacteria? a)Lackcellwall b)Cannotgrowincellfreeculturemedia c)Containsinclusionbody d)Noneoftheabove CorrectAnswer-CAns.is'c'i.e.,ContainsinclusionbodyChlamydiaproducesbasophilic(intracytoplasmic)inclusionbodiesininfectedcellsincontrasttoeosinophilicinclusionbodiesproducedbymostvirusesandhencetheyaresometimesreferredtoasBasophilicviruses.UniquepropertiesofchlamydiaeareChlamydiaisanobligateintracellularparasite.ThismeanstheycansurviveonlybyestablishigresidenceinsideanimalcellsTheyneedtheirhost'sATPasanenergysourcefortheirowncellularactivity.TheyareenergyparasitesusingacellmembranetransportsystemthatusesATPfromthehostsystemandgivesoutADP.Thisobligateintracellularexistencemakesitimpossibletoculturetheseorganismsonnonlivingartificialmedia.Duetotheirsmallsizeandfailuretogrowincell-freemediatheywereconsideredtobeviruses.ChlamydiaegrowsinculturesofavarietyofeukaryoticcelllinesMcCoyorHeLacells.ItmaybenecessarytotreatcellswithpolyanioniccompoundssuchasDEAD-dextrantoreducetheelectrostaticbarriertoinfection.Antimetabolitesuchascycloheximideisaddedtofavourcompetitionforhostcellaminoacidpools.Alltypesof
chlamydiaeproliferateinembryonatedeggsparticularyintheyolksac.Thespecialfeaturesinstructureandchemicalcompositionofchlamydiaeare: 1. Theoutercellwallresemblesthecellwallofgramnegativebacteria2. Ithasarelativelyhighlipidcontent3. Itisrigidbutitdoesnotcontaintypicalbacterialpeptidoglycan; perhapsitcontainatetrapeptidelinkedmatrix. 4. NAcetylmuramicacidalsoappearstobeabsentfromchlamydiae cellwall.
195.Apatientissufferingfrompneumonia. Laboratorystudyshowsacid-fastfilamentousbacterium.Thecausativeorganismis? a)M.tuberculosis b)Actinomyces c)Nocardia d)MycobacteriumAviumintracellulare CorrectAnswer-CAns.is'c'i.e.,NocardiaSymptomsofpneumoniabyafilamentousacidfastbacteriumsuggestthediagnosisofNocardia.
196.MycobacteriumtuberculosisgrowsinLJ mediain? a)10-14days b)2-3weeks c)4-8weeks d)>10weeks CorrectAnswer-CAns.is'c'i.e.,4-8weeksMtuberculosisproducesvisiblecoloniesonsolidmedia(L.J.media)in4-8weeksUseofliquidmediawithradiomimeticgrowthdetection(BACTEC-460)andtheidentificationofisolatesbynucleicacidprobesgiveresultin2-3weeks.
197.Whichofthefollowingisanexampleof heterophileantibodytest? a)Widaltest b)Weil-Felixreaction c)Rose-walertest d)Bloodgrouping&crossmatching CorrectAnswer-BAns.is'b'i.e.,Weil-FelixreactionHeterophilicagglutinationreactionSomeorganismsofdifferentclassorspeciessharecloselyrelatedantigens.Whenserumcontainingagglutinin(antibody)ofoneorganismgivesagglutinationreactionwithantigenofotherorganism,itiscalledheterophilicagglutinationtest.ExamplesareStreptococcusM.G.agglutinationtestforprimaryatypicalpneumonia.Weil-Felixreactionfortyphusfever.PaulBunnelltestforIM1V.
198.Allcauseviralhepatitisexcept- a)Measles b)EBV c)Rhinovirus d)Reovirus CorrectAnswer-CAns.is'c'i.e.,RhinovirusImportantvirusescausinghepatitis:?1)Hepatotropicviruses:HAV,HBV,HCV,HDV,HEV.2)Herpesviruses:CMV,EBV,HSV-1,VZV.3)Flaviviruses:Yellowfever,denguefever.4)Filoviruses:Marburgvirus,Ebolavirus.5)OccasinalcausesMeaslesvirus,adenovirus,Echoviruses,Coxsackieviruses,influenzavirus,parvoviruses,reoviruses,mumpsvirus.
199.Shigatoxinactsby? a)ActivatingadenylylcyclasetoincreasecAMP b)ActivatingguanylylcyclasetoincreasecGMP c)Inhibitingproteinsynthesis d)InhibitingDNAreplication CorrectAnswer-CAns.is'c'i.e.,Inhibitingproteinsynthesis
200.Enrichmentmediaforcholera? a)VRmedium b)TCBSmedium c)Cary-Blairmedium d)Alkalinepeptonewater CorrectAnswer-DAns.is'd'i.e.,Alkalinepeptonewater
201.Trueaboutvibrioparahemolyticus? a)Polarflagella b)Nonhalophilicvibrio c)Non-capsulated d)RequiresNaCI CorrectAnswer-DAns.is'd'i.e.,RequiresNaCIItishalophilicvibrio.*Inhabitsthecoastalsea,whereitisfoundinftshesarthopodssuchasshrimpsandctabsandmolluscssuchasoyster.*Itresemblesthecholeravibrioexceptthat:-->Itiscapsulated.-->Showsbipolarstaining*Producesperitrichousflagellawhengrownonsolidmediun(V.choleraehaspolarflagella),inliquidmediumpolarflagellaareformed.*Itgrows,onlyinmediacontainingNaCl,optimumconc.is2-4%,ltsenteropathogeniciscloselylinkedtoitsabilitytocausehemolysisonWagatsumaagarttheKanagawaphenomenon.
202.Selectivemediumforshigella? a)Chocolateagar b)BYCEmedium c)Hektoenagar d)EMJHmedium CorrectAnswer-CAns.is'c'i.e.,Hektoenagar
203.Sterilizationisdefinedas? a)Disinfectionofskin b)Completedestructionofallmicroorganisms c)Destructionofpathogenicorganisms d)Decreasebacterialcountfromobjects CorrectAnswer-BAns.is'b'i.e.,CompletedestructionofallmicroorganismsSterilizationTheprocessbywhichanarticlesurfaceormediumisfreedofalllivingmicroorganismseitherinthevegetativeorsporestateCompleteabsenceofmicroorganism.DisinfectionDestructionorremovalofallpathogenicorganismscapableofgivingrisetoinfectionreductioninthemicroorganismstosuchalevelwhichisdeemednolongerharmfultohealth.Unlikesterilization,disinfectionisnotsporicidal(doesnotkillspores).DecontaminationTheprocessofrenderingofanarticleorareafreeofdangerfromcontaminants,includingmicrobial,chemical,radioactiveandotherhazards.AntisepsisItisdefinedas"Preventionofinfection,usuallybyinhibitingthegrowthofbacteriainwoundortissues".AntisepticsChemicaldisinfectantswhichcanbesafelyappliedtoskinormucousmembranearecalledantisepticsorskindisinfactant.Bestandmostcommonlyusedantisepticispovidoneiodine
(betadine).Commonlyusedskindisinfactantsforhandwashingarepovidoneiodine(betadine),chlorhexidineandisopropylalcohol.DisinfectantsAntimicrobialsappliedonlytoinanimateobject.Theyarenotusedforsurfacedisinfection(A"9)(skinormucousmembrane).GermicidesTheseincludebothantisepticsanddisinfectant.
204.Trueaboutendotoxin? a)Protein b)Highlyantigenic c)Noenzymaticactivity d)Producedbygrampositivebacteria CorrectAnswer-CAns.is'c'i.e.,Noenzymaticactivity
205.A17yearsoldfemalepresentswithsore throat,lymphadenopathyandpositiveheterophileantibodiestest.Diagnosisis? a)Tuberculosis b)Streptococcalpharyngitis c)Infectiousmononucleosis d)Cytomegalicinclusiondisease CorrectAnswer-CAns.is'c'i.e.,InfectiousmononucleosisLaboratorydiagnosisInIMN,thereispredominantlylymphocytosiswithpresenceof20%ormoreatypicallymphocytes.TheseatypicallymphocytesareactivatedT-lymphocyteswhichhaveroundorirregularlyshapednuclei,withabundantflowingcytoplasmthatcharacteristicallyhasadark-stainingperipheri.
206.Lethaleffectofdryheatisdueto? a)Denaturationofproteins b)Oxidativedamage c)Toxicityduetometabolites d)Alloftheabove CorrectAnswer-DAns.is'd'i.e.,AlloftheaboveHEATSTERILIZATIONHeatisthemostreliablemethodofsterilisationandshouldbethemethodofchoiceunlesscontraindicated.oSterilizationbyheatisoftwotypes.DryheatKillingeffectisduetoproteindenaturation,oxidativedamageandthetoxiceffectofelevatedmetabolites.
207.PLETmediumisusedin? a)Plague b)Anthrax c)Typhoid d)Cholera CorrectAnswer-BAns.is`b'i.e.,AnthraxSelectivemediaforB.antracisisPLETmedium,consistingofpolymyxin,lysozyme,ethylenediaminetetraaceticacid(EDTA)andthallousacetateaddedtoheartinfusionagar.
208.Tunicareactionispositivein? a)Rprowazekii b)Rtyphi c)Rtsutsugamushi d)Rakari CorrectAnswer-BAns.is'b'i.e.,RtyphiNeill-Mooser(Tunica)reactionWhenmaleguineapigsareinoculatedintraperitoneallywithbloodfromacaseofendemictyphusorwithacultureofR.typhi(R.mooseri)theydevelopfeverandacharacteristicscrotalinflammation.ThisreactionisusedtodifferentiateR.typhiandR.prowazekii.
209.Laproscopeissterilizedby? a)2%formalin b)2%glutaraldehyde c)Autoclaving d)Boiling CorrectAnswer-BAns.is'b'i.e.,2%glutaraldehydeAllendoscopes(e.g.laproscope)aresterilizedby2%glutaraldehyde(cidex).
210.Sucklingmiceisusedforisolationof? a)Coxsachievirus b)Pox c)Herpes d)Adenovirus CorrectAnswer-AAns.is'a'i.e.,CoxsackievirusItisnecessarytoemploysucklingmicefortheisolationofcoxsackieviruses.Inoculationisusuallymadebyintracerebral,subcutaneousandintraperitonealroute.Adultmicearenotsusceptible.
211.Safetypinappearanceisseenin? a)Vibriovulnificus b)Vibrioparahemolyticus c)Pseudomonasaeuroginosa d)H.influenzae CorrectAnswer-BAns.is`b'i.e.,VibrioparahemolyticusBipolarstaining(safetypinappearance)Somebacteriadisplayasafetypinappearanceduetotheaccumulationofdyeatthepolesofthecells.Thischaracteristiciscalledbipolarstaining.Bacteriashowingbipolarstainingare? 1. Calymmatobactergranulomatis(Donovanigranulomatis)2. Vibrioparahemolyticus3. Pseudomonasmallei4. Yersiniapestis5. Pseudomonaspseudomallei6. H.ducreyi
212.Whichanticoagulantisusedwhenblood issentforbloodculture? a)Sodiumcitrate b)EDTA c)Oxalate d)SPS CorrectAnswer-DAns.is'd'i.e.,SPSManydifferenttypesofbacteriaandfungihavebeenidentifiedascausativeagentsofsepticemia.Forthisreason,manydiverseculturemediaformulationsareavailableinpreparedbloodculturebottles.Majorityofthesemediacontain0.03%SPS(Sodiumpolyanethalsulfonate),apolyanionicanticoagulant,whichadditionallyinhibitscomplementandlysozymeactivity,interfereswithphagocytosisandinactivatesaminoglycosides.Followingimportantbloodculturebottlesarethere:-i)Brainheartinfusion(BHI)withPABA(para-aminobenzoicacid)ii)Brucellabrothwith6%sorbitoliii)Brucellabrothwith10%sucroseiv)Columbiabrothv)Thioglycolatemediumvi)Trypticsoybroth
213.Kanagawa'sphenomenonisseenin? a)Pseudomoneaaeuroginosa b)Vibrioparahemolyticus c)Shigellasonie d)Proteusmirabilis CorrectAnswer-BAns.is'b'i.e.,VibrioparahemolyticusStrainsofvibrioparahemolyticusisolatedfrompatientsarealwayshymolyticonWagatsumaagar,whilestrainsfromenvironmentalsourcesarealwaysnon-hemolytic.ThislinkageofenteropathogenicitytoabilityofhemolysisonWagatsumaagariscalledKanagawa'sphenomenon.
214.Whichflaviviruscauseshepatitisin human? a)HepatitisA b)HepatitisB c)HepatitisC d)HepatitisD CorrectAnswer-CAns.is'c'i.e.,HepatitisC
215.Syncytiumformationisapropertyof? a)Herpesvirus b)Adenovirus c)Measlesvirus d)Rabiesvirus CorrectAnswer-CAns.is'c'i.e.,Measlesvirus
216.Babesiosisistransmittedby? a)Tick b)Mites c)Flea d)Mosquito CorrectAnswer-AAns.is'a'i.e.,TickBabesiaBabesiosisisaprotozoandiseasecausedbytwospeciesofBabesia:BabesiamicrotiandBabesiadivergens.ItistransmittedbyIoxdidtick.BabesiainfectstheRBCsandresidesinsidetheRBCs(intraerythrocytic).IntraerythrocyticinfectionofBabesiosisischaracterisedbymaltesecross.MaltesecrossisacharacteristicarrangementofparasiteswithintheerythrocytesParasiteswithinerythrocytesarearrangedsuchthatpointedendsoffourparasitescomeincontacttherebygivingatetradconfigurationresemblingamaltesecross.Tetradformsor'Maltesecross'appearanceisconsideredpathognomicofBabesiosis.ClinicallyBabesiosispresentswithchills,fever,mildhepatosplenomegaly,andmildhemolyticanemia.oTreatmentincludesAtovaquoneplusazithromycinorquinineplusclindamycin.BabesiosiscaneasilybeconfusedwithP.falciparummalaria.FollowingtwofeaturesdistinguishBabesiosisfrommalaria:? 1. PresenceofmaltesecrossinBabesiosis(absentinmalaria)2. AbsenceofpigmentHemozoininBabesiosis(presentinmalaria) Note-Maltesecrossisalsoseenincryptococcusandaspergillus.
217.Pseudomonasexotoxininhibitsprotein synthesisbyinhibiting? a)RNApolymerase b)EF-2 c)Transpeptidase d)Reversetranscriptase CorrectAnswer-BAns.is'b'i.e.,EF-2Exotoxin'A'ofP.aeruginosainhibitsproteinsynthesisthroughinterferencewithadenosinediphosphateribosylationofelongationfactor-2.RememberBacterialtoxinsinhibitingproteinsynthesis:ExotoxinAofPaeruginosaShigatoxin(Shigella)DiphtheriatoxinShigaliketoxinorverocytotoxinofEHEC.
218.Tripleironsugarmediumcontainsall, except? a)Lactose b)Sucrose c)Glucose d)Maltose CorrectAnswer-DAns.isdi.e.,MaltoseTriplesugarironagarisusedforthedifferentiationofmicroorganismsonthebasisof:? i. Fermentationofdextrose(glucose),lactoseandsucrose. ii. ProductionofH2S. Itisrecommendedfordifferentiationofentericgramnegativebacillifromclinicalspecimens,dairysamplesandfoodproducts.Contentsofthemediumare:? i. Enzymaticdigestofcaseinandanimaltissue. ii. Yeastenrichedpeptone. iii. Threesugars:Dextrose(glucose),lactoseandsucrose. iv. Ferricammoniumcitrate. v. Sodiumchloride. vi. Sodiumthiosulfate. vii. Phenolred. viii. Agar. Whencarbohydratesarefermented,acidproductionisdetectedbythephenolredindicator,whichisyellowinacidandredinalkalineconditions.Sodiumthiosulfateisreducedtohydrogensulfide(H2S)andH2S
reactswithanironsaltyieldingtypicalblackironsulfide.Ferricammoniumcitrateishydrogensulfideindicator.ResultsTwoareasoftubeareexamined:(i)Buttofthetube,and(ii)Slantofthetube.Analkalineslant(red)-acidbutt(yellow)indicatesfermentationofdextrose(glucose)onlyred/yellow.ExamplesareProteusmirabilis,salmonellathyphimuriumandshigellaflexneri.Anacidslant(yellow)-acidbutt(yellow)indicatesfermentationsofdextrose(glucose),lactoseand/orsucroseyellow/yellow.ExampleisEcoli.Analkalineslant(red)-alkalinebutt(red)indicatesnofermentation(non-fermenter)red/red.ExampleisPseudomonasaeruginosa.AnalkalineprecipitateinbuttindicatesH2Sproduction.ItisproducedbyProteusmirabilisandSalmonellatyphimurium.
219.FastestmethodfordiagnosisofTB- a)Geneexpert b)LJmedium c)TBMGIT d)BAC,IEC CorrectAnswer-AAns.is'a'i.e.,GeneexpertGeneXpertMTB/RIFTheXpertMTB/RIFdetectsDNAsequencesspecificforMycobacteriumtuberculosisandrifampicinresistancebypolymerasechainreaction.ItisbasedontheCepheidGeneXpertsystem,aplatformforrapidandsimple-to-usenucleicacidamplificationtests(NAAT).TheXpertMTB/RIFpurifiesandconcentratesMycobacteriumtuberculosisbacillifromsputumsamples,isolatesgenomicmaterialformthecapturedbacteriabysonicationandsubsequentlyamplifiesthegenomicDNAbyPCR.TheprocessidentifiesalltheclinicallyrelevantrifampicinresistanceinducingmutationsintheRNApolymerasebeta(rpoB)geneinthemycobacteriumtuberculosisgenomeinarealtimeformatusingfluorescentprobescalledmolecularbeacons.Resultsareobtainedfromunprocessedsputumsamplesin90minutes,withminimalbiohazardandverylittletechnicaltrainingrequiredtooperate.
220.NewYorkagarisusedfor? a)Salmonella b)Clostridia c)Neisseria d)BacillusAnthracis CorrectAnswer-CAns.is'c'i.e.,NeisseriaNewYorkCity(NYC)mediumisprimarilydesignedforisolationofpathogenicNeisseria.Italsosupportsthegrowthofgenitalmycoplasma(MycoplasmahominisandUreoplasmaUrealyticum).Itisusefulinthediagnosisofgonorrheaandmycoplasmainfection.Itconsistsofprimarilyapeptone-cornstarchagar-basebufferedwithphosphatesandsupplementedwithhorseplasma,horsehemoglobin,dextrose,yeastautolysateandantibiotics.
221.AcquireIgAdeficiencymayoccurin? a)SevereCongenitaltoxoplasmosis b)SevereMeaslesinfection c)SevereBrucellosis d)SevereLeptospirosis CorrectAnswer-ASevereCongenitaltoxoplasmosisBlockinBcelldifferentiationduetodefectiveinteractionbetweenTandBcells.NaiveBcellsarenotabletodifferentiateintoIgA-producingcells.
222.Whichofthefollowingisasexualspore ? a)Chlamydospore b)Sporangiospore c)Ascospore d)Phialoconidia CorrectAnswer-CAns.is'c'i.e.,Ascospore
223.TrueaboutNipahvirusareallexcept? a)Isaparamyxovirus b)Causeshemorrhagicfever c)Emerginginfection d)PresentinIndia CorrectAnswer-BAns.is'b'i.e.,CauseshemorrhagicfeverNipahvirusisanemerginginfectiousagentbelongstoparamyxoviridae.ItwasfirstisolatedinMalaysiain1998,causingencephalitisindomesticpigs,withdirecttransmissionfrompigstohuman.TherehavebeenNipahvirusinfectionoutbreaksinpigsinMalaysiaandSingaporeandhumandiseaseinMalaysia,Singapore,IndiaandBangladesh.Typicallythehumaninfectionpresentsasanencephalitissyndromemarkedbyfeverheadache,drowsiness,disorientation,mentalconfusion,comaanddeath.
224.Defectivehepatitisvirusis? a)HAV b)HBV c)HCV d)HDV CorrectAnswer-DAns.is'd'i.e.,HDVHepatitisD(HDV)orDeltavirusItisdefectiveRNAvirusdependentonthehelperfunctionofHBVforitsreplicationandexpression.ItcontainssinglestrandedRNA(ssRNA)-DefectiveRNA.IthasnoindependentexistenceandcansurviveandreplicateonlyaslongasHBVinfectionpersistsinthehost.Itresemblessomeplantviruses,suchasviroidsorsatelliteviruses.IthasbeenclassifiedingenusDeltavirus.DeltacoreofHDVisencapsidatedbyanouterenvelopeofHBsAg,soitrequirecooperativefunctionofHBV.IntracellularreplicationofHDVRNAcanoccurwithoutHBVbutliverinjuryrequiresthepresenceofHBV.HDVcancausetwotypesofinfection.
225.Thecysticformofallareseeninman except? a)E.histolytica b)Giardia c)Trichomonas d)Toxoplasma CorrectAnswer-CAns.is'c'i.e.,TrichomonasProtozoalparasiteshavetwophases.CysticphaseTrophozoiteCysticphaseisnotseenin:TrichomonasEntamoebagingivalisDientamoebafragilis
226.Maternalmortalityismorein? a)HAV b)HBV c)HCV d)HEV CorrectAnswer-DAns.is'd'i.e.,HEVHepatitisEvirusAlsoknownasentericallytransmittednon-Anon-B(NANB)virusorepidemicNANB.ItisclassifiedinthegenusHerpesvirusunderthefamilycaliciviridae.ItisaRNAviruswithsingle-strandedpositivesenseRNAItistransmittedbyfecal-oralroute.InIndia,HEVisresponsibleforthemajorityofepidemicandsporadichepatitisinadults.AnepidemiologicalfeaturethatdistinguishesHEVfromotherentericagentsistherarityofsecondarypersontopersontransmission(Secondaryattackrateisverylow2-3%asagainst10-20%inHAVinfection)Auniquefeatureistheclinicalseverityandhighcasefatalityrateof20-40%inpregnantwomen,especiallyinthelasttrimesterofpregnancy.Itischaracteristicallyassociatedwithcholestasis
227.Culturemediausedfor0157:H7Entero hemorrhagicEcoli? a)Sorbitolcontainingagar b)Mannitolcontainingagar c)Sucrosecontainingagar d)Dextrosecontainingagar CorrectAnswer-AAns.is'a'i.e.,SorbitolcontainingagarCultureof0157:H7E.coliE.coli0157:H7isnotidentifiedonroutinestoolcultures.E.coli0157:H7canbespecificallydetectedbytheuseofmodifiedMacConkeymediawhichcontainssorbitolinplaceoflactose(SMAC).SorbitolMacConkeymediaisspecificallyusefulforthedetectionofE.coli0157:H7asunlikemoststrainsofE.coli,the0157:H7straindoesnotfermentsorbitol.NonfermentingcoloniesonaSorbitolMacConkeyplate(SMAC)thereforesuggestthediagnosisofE.coli0157:H7.SorbitolMacConkeymediaisthescreeningmethodofchoiceforE.coli0157:H7.
228.Liquidmediumfortuberculosis? a)LJmedium b)Dorsetmedium c)Loeffler'smedium d)MGIT CorrectAnswer-DAns.is'd'i.e.,MGITMycobacterialgrowthindicatortube(MGIT)isanautomatedliquidculturemethod.Itcontains7mlofmodifiedMiddlebrook7H9Brothbase.
229.IndicatorusedinMaConkeyAgar? a)Methyleneblue b)Methylred c)Neutralred d)Bromothymolblue CorrectAnswer-CAns.is'c'i.e.,NeutralredMacConkeyagarisaselectivemediumforentericgramnegativebacilli.Itisusedtodifferentiatelactosefermentingentericbacillifromlactosenon-fermenters.CompositionofMacConkeyagar?1)Enzymaticdigestofgelatin,caseinandanimaltissue:Toprovidenutrition.2)Lactose:Fermentablecarbohydrate.3)Bilesalts:Selectiveagentandinhibitsgrampositiveorganisms.4)Crystalviolet:Inhibitsgrampositivebacteria.5)Sodiumchloride:Suppliesessentialelectrolytesandosmoticbalance.6)Neutralred:pHindicator(whenlactoseisfermented,thepHofmediumdecreases,changingcolorofneutralredtopink).7)Agar:Solidifyingagent.
230.Subterminalsporesareseenin? a)Clperfringens b)Cltetani c)Cltertium d)None CorrectAnswer-AAns.is'a'i.e.,Clperfringens
231.LGV(lymphogranulomavenerum)is causedby? a)Treponemapallidum b)Chlamydiatrachomatis c)Calymmatobactergranulomatosis d)HDucreyi CorrectAnswer-BAns.is'b'i.e.,ChlamydiatrachomatisLymphogranulomavenereum(LGV)isalong-term(chronic)infectionofthelymphaticsystem.Itiscausedbyanyof3differenttypes(serovars)ofthebacteriaChlamydiatrachomatis.Thebacteriaarespreadbysexualcontact.Theinfectionisnotcausedbythesamebacteriathatcausegenitalchlamydia.Chlamydiatrachomatiscauseseye(conjunctivitis,trachoma),respiratory(pneumonia),andgenitaltract(urethritis,lymphogranulomavenereum)infections.DiagnosismadewithnucleicacidtestforCtrachomatis,LGVserovarsdiagnosedserologically.
232.Exanthemasubitumiscausedby? a)HHV-6 b)HHV-8 c)Parvovirus d)Coxsackievirus CorrectAnswer-AAns.is'a'i.e.,HHV-6HHV-6causesroseolainfantum(alsocalledexanthemasubitumorsixthdisease).
233.Whichisnotparenterallytransmitted a)HAV b)HBV c)HCV d)HDV CorrectAnswer-AAns.is'a'i.e.,HAV
234.Trueaboutcryptococcusareallexcept a)Primarilyinfectslung b)Ureasenegative c)India-inkisused d)Allaretrue CorrectAnswer-BAns.is`bi.e.,UreasenegativeCRYPTOCOCCUSNEOFORMANSTheonlypathogenicyeastFourcapsularserotypes-A,B,CandDIthaspolysaccharidecapsuleMostinfectionsinimmunocompromizedpatientsarecausedbyserotypeA.PigeondroppingscommonlycontainsserotypeAandD.EucalyptustreecontainserotypeB.Itisureasepositive.ModeoftransmissionByinhalationofthefungusintothelung(mostcommon)Throughskinormucosa(sometimes).
235.Whichvaccinecancauseadverseeffects inpersonswithallergytoegg? a)Measles b)Rubella c)Rabies d)Mumps CorrectAnswer-CAns.is'c'i.e.,RabiesDuckembryoVaccinehaslessneuroparalyticcomplications,butcancauseallergicreactions.Personsallergictoeggs,shouldnotbegiventhisvaccine.RabiesVaccineRabiesvaccinesarefluidordriedpreprationoffixedvirusgrownintheneuraltissuesofrabbits,sheep,goats,miceorratsorinembryonatedduckseggorincellcultures.Inactivationofvirusiscommonlydonebytreatmentwithformalinor13.Propiolactone(B.P.L.)oAntirabiesvaccinefallintotwomaincategries.
236.SalmonellaeotherthanStyphiandS paratyphicause? a)Typhoidfever b)Entericfever c)Gastroenteritis d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,GastroenteritisSALMONELLOSISSalmonellosisisreferredtotheinfectioncausedbybacteriaofgenussalmonella.Salmonellosisisoftwotypes? 1. TyphoidalSalmonellosiscausedbyS.typhiandparatyphi'A','B'and 'C'(hasbeenexplained,seepreviousexplanations) 2. Non-typhoidalSalmonellosis Non-tvphoidalSalmonellosis(NTS)Itisthemostcommontypeofsalmonellosis(morecommonthantyphoidalsalmonellosis)CommonNTSspeciesare? i. S.enteritidis ii. S.heidelburg iii. S.hadar iv. S.typhimurium v. S.newport Unliketyphoidsalmonella(S.typhiandS.paratyphi),whereonlyreservoirishumans;non-typhoidalsalmonellacanbeacquiredfrommultipleanimalreservoirs.Transmissionismostcommonlyassociatedwith?
i. Animalfoodproductsespeciallyeggs,poultry,undercookedmeat ii. Dairyproducts iii. Freshproducecontaminatedwithanimalwaste
237.OptimalpercentageofNaCIforV cholerae? a)1% b)2% c)3% d)4% CorrectAnswer-AAns.is'a'i.e.,1%
238.Waterhouse-Friderichsensyndromeis seenin? a)Pneumococci b)N.meningitidis c)Pseudomonas d)Yersinia CorrectAnswer-BAns.is'b'i.e.,N.meningitidisWaterhouse?Friderichsensyndrome(WFS)isdefinedasadrenalglandfailureduetobleedingintotheadrenalglands,commonlycausedbyaseverebacterialinfection.Typically,itiscausedbyNeisseriameningitides.Thebacterialinfectionleadstomassivebleedingintooneor(usually)bothadrenalglands.Fulminantmeningococcemia(purpurafulminansorWaterhouse-Friderichsensyndrome)isthemostrapidlylethalformofsepticshockexperiencedbyhumans.Itdiffersfrommostotherformsofsepticshockbytheprominenceofhemorrhagicskinlesions(petechiae,purpura)andtheconsistentdevelopmentofDIC.
239.CausativeorganismofSARS a)HiN, b)Coronavirus c)Rotavirus d)RSV CorrectAnswer-BAns.is'b'i.e.,CoronavirusSevereacuterespiratorysyndromeInNovember2002,ChinaexperiencedanoutbreakofanunusualrespiratoryinfectionwithmanydeathsSevereacuterespiratorysyndrome(SARS).oItiscausedbyCoronavirustype?4.SARSspreadsbyinhalationoftheviruspresentindropletsoraerosolsofrespiratorysecretionsofpatients.Fecalaerosolsmayalsobeinfectious.oIncubationperiodislessthan10days.
240.Weilfelixreactionisheterophile antibodiesreactionduesharingofRickettsialantigenwith a)Shigella b)Proteus c)Chlamydia d)Mycoplasma CorrectAnswer-BAns.is'b'i.e.,ProteusWeilfelixreactionThisreactionisanagglutinationtestinwhichseraaretestedforagglutininsto0antigensofcertainnonmotileproteusstrainsOX-19,OX-2andOX-K.Thebasisofthetestisthesharingofanalkali-stablecarbohydrateantigenbysomerickettsiaeandbycertainstrainsofproteus,P.vulgarisOX-19andOX-2andP.mirabilisOX-K.Thetestisusuallydoneasatubeagglutination,thoughrapidslideagglutinationmethodshavebeenemployedforscreening
241.Neutrilizationtestis a)Widaltest b)Weil-Felixtest c)PaulBunneltest d)Naglerreaction CorrectAnswer-DAns.is`d'i.e.,NaglerreactionNeutralizationreactionWhenantibodyreactswithatoxinorotherbiologicallyactiveantigen,itmayneutralizetheeffectoftoxinorantigen.Thisabilitytousedinneutralizationtest.Neutralizationtestsareoftwotypes
242.ModeoftransmissionofListeria a)Ingestion b)Inhalation c)Skininoculation d)None CorrectAnswer-AAns.is'a'i.e.,IngestionLISTERIOSISModeoftransmission;FoodborneMostcommon(mostcasesareduetoserotype4b)NosocomialInlate-onsetneonatalinfection.Lmonocytogenesentersthebodythroughthegastrointestinaltractafteringestionofcontaminatedfoodssuchascheese,fruit,orvegetables.Theorganismhasseveraladhesionproteins(Ami(anautolysinamidase),FbpA(fibronectinbindingprotein),andflagellinproteins)thatfacilitatebacterialbindingtothehostcellsandthatcontributetovirulence.Ironisanimportantvirulencefactor.Listeriaproducessiderophoresandisabletoobtainironfromtransferrin.
243.Frischbacillusaffectsmostcommonly a)Mouth b)Nose c)Eye d)Ear CorrectAnswer-BAns.is'b'i.e.,NoseFrischbacillusisKlebsiellarhinoscleromatis,whichcausesrhinoscleroma,agranulomatousdiseaseofthenose.Kpneumoniaesubspeciesrhinoscleromatisformrhinoscleroma,adestructivegranulomaofthenoseandpharynx.Klebsiellagranulomatis(formerlyCalymmatobacteriumgranulomatis)causesachronicgenitalulcerativedisease,granulomainguinale,anuncommonsexuallytransmitteddisease
244.Scarletfeveriscausedby a)Streptococcusagalactie b)Streptococcuspyogenes c)Streptococcuspneumoniae d)Streptococcusequisimilus CorrectAnswer-BAns.is'b'i.e.,StreptococcuspyogenesInfectionscausedbystreptococcuspyogenesScarletfeverconsistsofstreptococcalpharyngitis,accompaniedbyacharacteristicrashwhichhasatinyredpinpointappearancewithsand-paperliketexture.ItoccursduetoproductionoferythrogenictoxinRespiratoryinfectionsSorethroatisthemostcommonofstreptococcaldisease.Itmaybelocalisedastonsillitisasinolderchildrenandadultsoritmayinvolvethepharynxmorediffusely(pharyngitis)asinyoungerchildren.Otitismedia.
245.Eantigen(HBeAg)ofhepatitisBvirusis aproductofwhichgene a)S b)C c)p d)x CorrectAnswer-BAns.is'b'i.e.,CGenes&geneproductsThegenomeofHBVismadeofcircularDNA,butitisunusualbecausetheDNAisnotfullydoublestranded-->oneofthestrandsisincompleteandotheriscompletepartiallydoublestrandedDNA.Therearefourknowngenesencodedbygenome-->'C',X',`P','S'.
246.WhichtypeofpulmonaryTBismost likelytogivesputumpositive? a)Fibronodular b)Pleuraleffusion c)Cavitary d)None CorrectAnswer-CAns.is'c'i.e.,CavitarySputumsmearsareusuallypositiveinpatientswithlaryngealTB,endobronchialTBandcavitarypulmonaryTB"--Kelley's"PatientswithcavitarypulmonaryTBhavehighbacterialloadintheirsputum"--Internet
247.Mosthalophilicvibrio? a)Vcholerae b)Vvulnificus c)Valginolyticus d)Vparahemolyticus CorrectAnswer-CAns.is'c'i.e.,ValginolyticusValginolyticusismostsalttolerant(mosthalophilic)speciesofvibrio.
248.Bileesculinagarisusedfor? a)GroupAstreptococcus b)GroupBstreptococcus c)GroupCstreptococcus d)Enterococcus CorrectAnswer-DAns.is'd'i.e.,EnterococcusEnterococcusMajorityoftheinfectionsarecausedbyE.faecalisandE.faecium.LessfrequentlyisolatedspeciesareE.gallinarum,E.durans,E.hiraeandE.avium.Enterococciarenormalinhabitantsofthelargebowelofhumanadults,althoughtheyusuallymakeup<1%oftheculturableintestinalmicroflora.Theyarecatalasenegative(asallstreptococci).Theircharacteristicfeatureisthattheycangrowinpresenceof:? 1. 40%bile2. 6.5%Sodiumchloride3. AtpH9.64. At45?C(relativeheatresistantsurving60?Cfor30minutes)5. In0-1%methylenebluemilk Theyhydrolyzeesculin.Theygrowinpresenceof40%bileandhydrolyzeesculinBileesculinpositive.TheyarePYR(PyrrolidonylArylamidase)positive.Theyareusuallynon-hemolytic(gamma-hemolytic),butsome-timesmayshowalphaorbetahemolysis.
249.Tachyzoitesareseenin? a)Toxoplasma b)Toxocara c)Pulmonaryeosinophilia d)Ascaris CorrectAnswer-AAns.is'a'i.e.,ToxoplasmaToxoplasmosisisthediseasecausedbyinfectionwiththeobligateintracellularparasiteToxoplasmagondii.TherearetwodistinctstagesinthelifecycleofTgondii:?NonfelinestageInthisstagetissuecysts(containgbradyzoites)orsporulatedoocystsareingestedbyintermediatehosts(Human,mouse,sheeporpig).Thecystisrapidlydigestedbytheacidic-pHgastricsecretionreleasingbradyzoitesorsporozoites.Thesebradyzoitesorsporozoitesenterthesmall-intestinalepitheliumandtranformintorapidlydividingtachyzoites(endozoites).Thetachyzoitescaninfectandreplicateinallmammaliancellsexceptredbloodcells.Tissuecystscontainingmanybradyzoitedevelop7-10daysaftersystemictachyzoiteinfection.ThesetissuecystsoccurinavarietyofhostorgansbutpersistprincipallywithintheCNSandmuscle.Felinestage(sexualstage)Thisstagetakesplaceinthedefinitivehost(cat)Thiscycleisassociatedwithformationofoocysts,whichare
excretedincatfeces.Matureoocystscontain2sporocysts,eachwith4sporozoites.Theformationoftissuecystsincatsconstitutestheotherpartoffelinecycle.
250.Apatientpresentswithheadache,high feverandmeningismus.Within3dayshebecomesunconscious.Mostprobablecausativeagent? a)Naegleriafowleri b)Acanthamoebacastellani c)Entamoebahistolytica d)Trypanosomacruzi CorrectAnswer-AAns.is'a'i.e.,NaegleriafowleriAmongstthegivenoptionsNaeglariaandAcanthamoebacauseamoebicencephalitis."TheprognosisofNaeglariaencephalitisisuniformalypoor,mostpatientsdiewithinaweek"."Acanthamoebaencephalitisfollowsamoreindolentcourse".
251.DNApolymeraseofHBVisencodedby whichofthefollowing? a)Sgene b)Cgene c)Pgene d)Xgene CorrectAnswer-CAns.is`c'i.e.,PgeneDNApolymeraseofHBVisencodedbyPgene
252.Heatlabileliquidsaresterilizedby? a)Hotairoven b)Autoclaving c)Membranefilter d)Moistheat CorrectAnswer-CAns.is'c'i.e.,MembranefilterFiltersareusedtosterilizeheat-labilesolutions.Membranefiltersareusedtosterilizepharmaceuticalsubstances,ophthalmicsolutions,liquidculturemedia,oils,antibioticsandotherheatsensitivesolutions.
253.Rideal-Walkercoefficientisrelatedwith ? a)Disinfectingpower b)Parasiticclearance c)Dietaryrequirement d)Statisticalcorrelation CorrectAnswer-AAns.is'a'i.e.,DisinfectingpowerTraditionaltestingofdisinfectantsTwotraditionaltestsfordeterminingtheefficiencyofdisinfectantsare:?1)Rideal-Walkertest:Phenolistakenasthestandardwithunitasphenolcoefficient(pheno1=1)2)Chick-Martintest:Thedisinfectantactsinthepresenceoforganicmatter(driedyeastorfeces).
254.Apatientpresentswithfever.Peripheral smearsshowsbandacrosstheerythrocytes.Diagnosisis? a)PFalciparum b)Pvivax c)Povate d)Pmalariae CorrectAnswer-DAns.is'd'i.e.,PmalariaeBandacrosserythrocytes(band-formtrophozoites)ischaracteristicofPmalariae.
255.Rashisnotcausedby? a)Salmonella b)Shigella c)Meningococci d)Staphylococcus CorrectAnswer-BAns.is'b'i.e.,ShigellaSalmonella(typhoid)andmeningococcicausemorbiliformrash.StaphylococcuscausesscarlentiformrashinTSSandSSSS. InfectionscausingExanthems(acutegeneralizedrash) MorbilliformViral:Measles(rubeola),rubella,erythemainfectiosum,EBV,CMV,adenovirus,echovirus,earlyHIV,coxasackievirus.Bacterial:Typhoid,Earlysecondarysyphiis,Earlyrickettsia,Earlymeningoccemia.ScarlentiformScarletfever(streptococcus).Toxicshocksyndrome.Staphylococcalscaldedskinsyndrome.
256.Owleyeintranuclearinclusionbodyis seenin? a)Herpeszoster b)Herpessimplex c)CMV d)EBV CorrectAnswer-CAns.is'c'i.e.,CMVCYTOMEGALOVIRUS(CMV)AlsoknownassalivaryglandvirusCMVisthelargestvirusamongstherpesvirusesTheyarecharacterizedbyenlargmentofinfectedcells(cytomegaliccells)andintranuclearinclusions.Intranuclearinclusioniseccentricallyplacedandissurroundedbyahalo-owl'seyeappearanceOnceinfectedanindividualcarriesCMVforlifeCMVisthemostcommonorganismcausingintrauterineinfection.CMVisthemostcommonpathogencomplicatingorgantransplantation.
257.ParasitesforwhichmodifiedZNstainis used? a)Isospora b)Microsporidia c)Plasmodium d)Echinococcus CorrectAnswer-AAns.is'a'i.e.,Isospora
258.Mostcommoncomplicationofchicken- pox- a)Bacterialinfection b)Meningitis c)Pneumonia d)Nephritis CorrectAnswer-AAns.is'a'i.e.,BacterialinfectionComplicationsofchickenpoxThemostcommoninfectiouscomplicationofvaricellaissecondarybacterialsuperinfectionoftheskin,whichisusuallycausedbystreptococcuspyogenesorStaphylococcusaureus.ThemostcommonextracutaneoussiteofinvolvementinchildrenisCNS.Varicellapneumoniaisthemostseriouscomplicationfollowingchickenpoxinadults.
259.Manhaduncookedmeatatdinner3days back,Nowpresentingwithdiarrhea.StoolexaminationshowscomashapedorganismwithRBCandWBC.Causativeorganismis? a)Vibriocholerae b)Shigella c)Campylobacterjejuni d)Yersiniaenterocolitia CorrectAnswer-CAns.is'c'i.e.,CampylobacterjejuniThisisacaseofdysentery(RBCinstoolsalongwithWBC).Amongthegivenoptions,'b','c'and'd'cancausedysentery.But,comashapedorganismiscampylobactorjejuni.Basedonthedepthofintestinalinvasion,therearedifferentclinicalmanifestationsofinfectionwithorganismscausingdiarrhea:-Nocellinvesion(noninflammatory)Thebacteriabindtointestinalepithelialcellsbutdonotenterthecell.Diarrheaiscausedbythereleaseofenterotoxins.Waterydiarrheawithnofecalleukocytesandnosystemicsymptoms(e.g.fever)occurs.Organismsare: 1. Vcholerae2. Clostridiumperfringens3. Cryptosporidia
4. Adenovirus5. ETEC6. B.cereus7. Microsporidia8. Staph.aureus9. Giardia 10. Rotavirus Invasionoftheintestinalepithelialcells(Inflammatory)Theorganismshavevirulencefactorsthatallowbindingandinvasionintocells.Toxinsmaybethenreleasedthatdestroythecell.Thecellpenetrationresultsinasystemicimmuneresponsewithfecalleukocytesaswellasfever.ThecelldeathresultsinRBCleakageintothestool(dysentery).
260.Ecolicausinghemolyticuremic syndrome? a)Enteropathogenic b)Enterotoxigenic c)Enteroinvasive d)Enterohemorrhagic CorrectAnswer-DAns.is'd'i.e.,EnterohemorrhagicSCHERICHIACOLIAtleastsixdistinct"pathotypes"ofintestinalpathogenicE.coliexist:EnteropathogenicE.colilEnteroadherentE.colilItcausesdiarrhoeaininfantsandchildrenusuallyoccuringasinstitutionaloutbreaks.Itdoesnotproduceenterotoxin,noraretheyinvasive.Theyadheretothemucosaofsmallintestineandcausedisruptionofthebrushbordermicrovilli.ThesestrainscanbeidentifiedbytheiradhesiontoHEP-2cells.EnterotoxigenicE.coliItcausestraveller'sdiarrhoea[ETECisthemostcommoncauseoftraveller'sdiarrhea!.Itproducesenterotoxins.Theycanproduceheatlabiletoxin(LT)orheatstabletoxinorboth.Toxinproductionalonemaynotleadtoillness.Thestrainshouldfirstbeabletoadheretointestinalmucosa.Thisadhesivenessismedicatedbyfimbrialorcolonisationfactorantigen(CFA).EnteroinvasiveE.coliTheythemselvesresembleshigellaandtheirinfectionresembles
shigellosis(remember:shigaliketoxiniselaboratedbyenterohemorrhagicE.coli).Theyproducemilddiarrhoeatofrankdysentryandoccurinadultaswellasinchildren.TheyhavebeentermedenteroinvasivebecausetheyhavethecapacitytoinvadeintestinalepithelialcellsinvivoandpenetrateHeLaorHEP-2cellsintissueculture.Thisabilityofpenetrationisplasmiddeterminedwhichcodesforoutermembraneantigenscalledthe'virulencemarkerantigen'(VMA).Thedetectionofplasmidcanbediagnostic.ForlaboratorydiagnosisofEIEC,theserenytestusedtobeemployed.Thesestrainsarenonmotile,donotfermentlactoseorfermentitlatewithacidwithoutproducinganygas.EnterohemorrhagicE.coliorverotoxigenicE.coliThesestrainsproduceverocytotoxin(VT)orshigaliketoxin(SLT)Theycancausemilddiarrhoeatofatalhemorrhagiccolitis.Shigaliketoxinbelongstoclassribosomeinactivatingproteins(RIPs).Itinhibitsproteinsynthesisbyinhibitingribosomalfunction.ThistoxinalsoactsonvascularendotheliumtopromotethesynthesisofcoagulationfactorVIII,vWF-*Plateletaggregation.Theycancausehemolyticuremicsyndromeparticularlyinyoungchildrenandtheelderly.0157:H7isthemostprominentserotypeofEHEC,associatedwithHUS,but06,026,055,091,0103,0111,0113andOX3havealsobeenassociatedwiththissyndrome.TheprimarytargetforVTisvascularendothelium.ThetypicalEHECisserotype0157:H7whichdoesnotferementsorbitalunlikemajorityofE.coli(butHarrisonwritesthatfewspeciesofthisserotypecanfermentsorbital).Someotherserotypelike026:H1alsobelongstothisgroup.LaboratorydiagnosisofVIECdiarrheaisestablishedbydemonstrationofthebacilliorVTinfecesdirectlyorinculture.
261.KOHwetmountispreparedfor? a)HerpesZoster b)Candida c)Gonorrhea d)Trichomonasvaginalis CorrectAnswer-BAns.is'b'i.e.,Candida
262.OncogenicDNAvirusis? a)Retrovirus b)HBV c)HIV d)HTLV CorrectAnswer-BAns.is'b'i.e.,HBV
263.BandformofPmalariaeis? a)Schizointstage b)Trophozoitestage c)Merozoitestage d)Gametocytestage CorrectAnswer-BAns.is'b'i.e.,Trophozoitestage
264.Bifringencepolarizationmicroscopyis usedfor? a)Flagella b)Intracellularstructures c)Capsule d)Spores CorrectAnswer-BAns.is`b'i.e.,IntracellularstructuresPolarizationmicroscopeenablesthestudyofintracellularstructureusingdifferencesinbifringence.
265.Mostcommoncauseofinfectiondueto catheterinurinarytract? a)Ecoli b)Coagulasenegativestaphylococci c)Staphaureus d)Pseudomonas CorrectAnswer-AAns.is'a'i.e.,Ecoli"Ecolicause80%ofacuteUTIinpatientswithoutcatheterization"."E.coilisthemostcommoncauseofcatheterassociatedUTItoo".
266.Whichofthefollowingfungiis/are difficulttoisolateculture? a)Candida b)Dermatophytes c)Cryptococcus d)Malasseziafurfur CorrectAnswer-DAns.is'D'i.e.,MalasseziafurfurMalasseziafurfurdoesnotgrowonregularsabouraud'smedium.ItrequirescomplexmediatogrowM.furfurisalipiddependentfungusand1%emulsifiedoliveoilisaddedtosabouraudmediumforitscultivationTwomediaarenowwidelyemployedforallmalasseziaspecies. 1. Dixonmedium2. Modifieddixonmedium
267.WindowperiodinHIVinfection? a)1-2weeks b)4-8weeks c)8-12weeks d)>12weeks CorrectAnswer-BAns.is'b'i.e.,4-8weeksWindowperiodIttakes2-8weekstomonthsforantibodiestoappearafterinfection.Thisperiod,frominfectiontoappearanceofantibodies,iscalledaswindowperiod.Duringthisperiodpatientsisseronegativei.e.serologicaltests(ELISAandWesternblot)arenegative.oTheindividualmaybehighlyinfectiousduringthisperiod.
268.Thermophilebacteriagrowat? a)20?C b)20-40?C c)40-60?C d)60-80?C CorrectAnswer-DAns.is'd'i.e.,60-80?CTemperaturerequirementofbacteriaBacteriavaryintheirrequirementsoftempratureforgrowth. 1. Psychrophilicbacteriagrowbestattemperaturebelow20?C2. Thermophilicbacteriagrowbestbetween55-80?C3. Mesophilicbacteriagrowbestbetween25-40?C
269.Whichofthefollowingisnotapox virus? a)Cowpox b)Molluscumcontagiosum c)Smallpox d)Chickenpox CorrectAnswer-DAns.is'd'i.e.,ChickenpoxPoxvirusescausingdiseaseinhumansVariola(smallpox)BuffalopoxCowpoxMolluscumcontagiosumVacciniaMonkeypoxOrfTanapoxChickenpoxiscausedbyvaricella-zostervirus,whichisaherpesvirus.
270.Metachromaticgranulesareseenin? a)Gardenellavaginali b)Corynebacteria c)Argobacterim d)Alloftheabove CorrectAnswer-DAns.is'd'i.e.,AlloftheabovePolvpmetahosphate/volutingranulesSomebacteriacontaingranulescomposedofpolymetaphosphate.Theywerefirstdescribedinspirillumvolutans,sotheywerecalledasVolutingranules.ThesegranulesarealsoknownasBabesErnstgranulesorpolarbodiesormetachromaticgranules.Thesegranulesstainreddishvioletwithmethyleneblueortoluidineblue.Thesegranulesarestronglybasophilic.Inthegranules,thereisstoredphosphateintheformoflinearchainsofinorganicphosphate.Thesegranulesrepresentintracellularphosphatereservewhennucleicacidsyntheisdoesnotoccur.Thephosphateisincorporatedintonucleicacidduringthesynthesisofthelatter.Whennucleicacidsynthesisispreventedbystarvation,thegranulesaccumulateinthecytoplasm.So,volutinmetachromaticgranulesaremostfrequentincellsgrownunderconditionsofnutritionaldeficiency(starvation)andtendtodisappearwhenthedeficientnutrientsaresupplied.Volutinmetachromaticgranulesarecommonin-
i. Corynebacteriadiptheriae ii. Gardenellavaginalis iii. Agrobacterimtumefaciens iv. Mycobacteria v. Spirillumvoluants
271.Whichofthefollowingisincubatedat temperature40-44degrees? a)Vibriocholerae b)Pseudomonasaeruginosa c)Vibrioparahemolyticus d)Ecoli CorrectAnswer-BAns.is'b'i.e.,Pseudomonasaeruginosa"Theoptimumtemperatureforgrowthofpseudomonasaeruginosais37degreeandisabletogrowattemperatureashighas42?C"-EssentialsofMicrobiologyPseudomonasaeruginosaMorphologyGramnegativebacilliMotilebypolarflagellumNoncapsulatedbutmanystrainshavemucoidslimlayerespeciallytheorganismswhichareisolatedfromcysticfibrosispatient.CultureObligateaerobeColoniesemitadistinctive,musty,mawkish,earthyorsweetgrape-likeodourorcorntocolikeodour.Cetrimideagarisaselectivemedia.Pseudomonasaeruginosaproducesanumbersofpigments.Theproductionofthesepigmentsaccountsforthecolourofcolonies.PyocyaninisproducedonlybyP.aeruginosaanditinhibitsthegrowthofmanyotherbacteria.Pyoverdinmaybeproducedbymanyotherspecies.
272.Transmissionofcholeraisthrough? a)Fecallycontaminatedfood b)Fecallycontaminatedwater c)Contaminatedfoodbyvomitsofacase d)Alloftheabove CorrectAnswer-DManistheonlyreservoir.Theimmediatesourceofinfectionarethestoolsandvomitsofcasesandcarrier.Infectionisacquiredthroughfecallycontaminatedwaterorfood.ChlorinationofwateriseffectiveagainstVcholerae.Therearefollowingtyesofcarrierincholera.i)Incubatory:Shedvibriosonlyinthebriefincubationperiodof1-5days.ii)Convalescent:Shedvibriosfor2-3weeks.iii)Healthyorcontactcarrier:Hashadsubclinicalinfectionandshedvibriosforlessthan10days.iv)Chroniccarriers:Canshedvibriosformonthsoryearsandmayhavepersistentinfectioningallbladder.
273.Reservoirofplagueis? a)Domesticrat b)Wildrat c)Ratflea d)Man CorrectAnswer-BAns.is'b'i.e.,Wildrat
274.IgEbindstowhichcell? a)Tcells b)Bcells c)Mastcells d)NKcells CorrectAnswer-CIgEbindstoMastcellsandbasophils,andmediateTypeIhypersensitivity.
275.Wrongstatementaboutchickenpox/ herpeszoster? a)CausedbyVZV b)Chicken-poxprimaryinfection c)Herpes-zosterrecurrentinfection d)Latentinfectionintrigeminalganglion CorrectAnswer-CAns.is'c'i.e.,Herpes-ZosterrecurrentinfectionHerpes-Zosterisduetoreactivationoflatentinfection(notduetorecurrentinfection).Otheroptionsarecorrect.
276.Sterolsarefoundin? a)CellwallofRicketssia b)CellmembraneofRicketssia c)CellwallofMycoplasma d)CellmembraneofMycoplasma CorrectAnswer-DAns.is'd'i.e.,CellmembraneofMycoplasmaMycoplasmalackcellwall.Theyareboundedbytriplelayeredunitmembranethatcontainssterol.oThustheyrequirecholesteroleandrelatedsterols.
277.Doublezoneofhemolysisisseenin? a)Staphylococcusareus b)Streptococcuspyogenes c)Clostridiumperfringens d)Corynebacteriumdiphtheriae CorrectAnswer-CAns.is'c'i.e.,ClostridiumperfringensTwoimportantcharacteristicfeatureofCl.perfringensare:? 1. Targethemolysis(doublezonehemolysis)onbloodagar.Itisa narrowzoneofcompletehemolysisbythetatoxinwhichissurroundedbyawiderincompletehemolysisbyalpha-toxin. 2. Naegler'sreactiondetectsalphatoxin(phospholipaseorlecithinase C).WhenCL.perfringensisgrownonamediumwiththeantitoxinspreadononehalfoftheplate,coloniesontheotherhalfwithouttheantitoxinwillbesurroundedbyazoneofopacity.Therewillbenoopacityaroundthecoloniesonthehalfoftheplatewiththeantitoxin,duetothespecificneutralisationofthealpha-toxin.
278.Mechanismactionofbotulinumtoxin? a)IncreasedcAMP b)IncreasedcGMP c)Inhibitionofacetylcholinerelease d)Inhibitionofnoradrenalinerelease CorrectAnswer-CAns.is'c'i.e.,InhibitionofacetylcholinereleaseBotulinumToxinCl.botulinumproducesapowerfulexotoxinthatisresponsibleforitspathogenicity.Thetoxindiffersfromotherexotoxinsinthatitisnotreleasedduringthelifeoforganism.Itisproducedintracellularlyandappearsinthemediumonlyonthedeathandautolysisofthecell.Itisthemosttoxicsubstanceknown.Toxinisheatlabile,butsporesarehighlyheatresistant.Itactsbyblockingthereleaseofacetylcholineatsynapsesandneuromuscularjunction.Itactspresynaptically.Toxinofalltypes(A,B,C,D,E,F,G)areneurotoxinexceptC2whichisacytotoxin(enterotoxin).
279.SerummarkerafterHepatitisB vaccination? a)Anti-HBsAg b)Anti-HBeAg c)Anti-HBcAg d)HBsAg CorrectAnswer-AAns.is'a'i.e.,Anti-HBsAg
280.DoublestrandedRNAviruswith segmentedgenome? a)Influenza b)Rotavirus c)Arenavirus d)Bunyavirus CorrectAnswer-BAns.is'b'i.e.,Rotavirus
281.Culturemediumforcampylobactorjejuni ? a)BYCEmedium b)Skirrow'smedium c)Thayer-Martinmedium d)TCBSmedium CorrectAnswer-BAns.is'b'i.e.,Skirrow'smedium
282.Allaretrueaboutcandidaexcept? a)Pseudohyphaeseen b)Producechlamydospore c)Itisamould d)Itisadimorphicfungus CorrectAnswer-CAns.is'c'i.e.,ItisamouldCandidaCandidaisayeastlikefungus(notmould).Candidaalbicansisthemostcommoncauseofmucosalcandidiasis.Allcandidaspeciespathogenicforhumansarealsoencounteredascommensalsofhumans,particularlyinthemouth,stoolandvagina.Theygrowrapidlyonsimplemediaasovalbuddingcellsat25?to37?C.Intissue,bothyeastsandpseudohyphaearepresent.Candidaalbicansisdifferentiatedbyothercandida:Itformstruehyphae(mycelia)orgermtubeswhengrowninserum.Itformsthickwalledlargesporescalledchlamydosporeswhengrownincornmealagar.Itisdimorphic.RememberCandidaalbicanscanproduceyeast,truehyphaeandpseudohyphae.ArapidmethodofidentifyingC.albicansisbasedonitsabilitytoformgermtubeswithintwohourswhenincubatedinhumanserumat37?CReynolds-Braudephenomenon(Alsoknownasgermtubetest)
283.Intermediatehostforguineaworm? a)Fish b)Man c)Cyclops d)Crab CorrectAnswer-CAns.is'c'i.e.,Cyclops
284.Whichofthefollowinghepatitisviruses isaDNAvirus? a)HepatitisCvirus b)HepatitisBvirus c)Deltaagent d)HepatitisEvirus CorrectAnswer-BAns.is'b'i.e.,HepatitisBvirusHepatitisBvirus(HBV)HepatitisBvirusisthemostwidespreadvirusandthemostimportantcauseofviralhepatitis.oHBVbelongstoHepadnaviridaeHBVishepadnavirustype-1HepatitisBistheonlyhepatitisviruswhichhasDNA.AllothersareRNAviruses.HBVcontainstwolinearstrandsofDNA.Oneofthestrands(theplusstrand)isincompleteandotheriscomplete(theminusstrand)PartiallydoublestrandedDNA.HBVcontainsbothDNA-dependentDNApolymeraseandRNAdependentreversetranscriptase.InsteadofDNAreplicationdirectlyfromaDNAtemplate,HBVrelysonreversetranscriptionofminusstrandDNAfromapregenomicRNAintermediate(likeretrovirus).
285.MostcommonNosocomialinfection? a)Pneumonia b)UTI c)Surgicalwoundinfection d)Nephritis CorrectAnswer-BAns.is'b'i.e.,UTIMostcommonnosocomialinfectionUrinarytractinfection.MostofthenosocomialUTIsoccurafterurinarycatheterization.SecondmostcommonnosocomialinfectionPneumonia.Mostofthenosocomialpneumoniasareacquirethroughrespiratoryintubation,mechanicalventilationandsuctionofthematerialfrommouth.
286.Methodusedforacidfaststaining? a)Robertson'smethod b)ZiehlNeelsen c)Silverimprignationmethod d)Darkgroundillumination CorrectAnswer-BAns.is'b'i.e.,ZiehlNeelsenAcidfaststainingAfterstainingwithanilinedye,acidfastorganismsresistdecolourisationwithacids.MethodmostcommonlyusedismodifiedZiehlNeelsen.
287.Paralysisinpolioischaracterizedby? a)Spasticity b)Symmetrical c)LMNtype d)Progressive CorrectAnswer-CAns.is'c'i.e.,LMNtypeClinicalmanifestationsofpolioIncubationperiodrangesfrom3-35days(usually7-14days).Theclinicalspectrumincludes:- 1. Subclinical(inapparent)infections(95%):Mostcommonandplay predominantroleinspreadofinfection. 2. Minor(abortive)illness(4.8%):Presentwithfever,sorethroat, headacheandmalaise. 3. Asepticmeningitis/nonparalyticpolio(1%):Therearesignsand symptomsofmeningitis. 4. Paralyticpolio(Thereisflaccidparalysiswithabsentreflexes. Respiratoryparalysisisthemostcommoncauseofdeath.
288.DrugresistanceinTuberculosisisdueto ? a)Transformation b)Transduction c)Conjugation d)Mutation CorrectAnswer-DAns.is'd'i.e.,Mutation
289.Allselectivemediaarecorrectlymatched except? a)Vcholerae-TCBSmedium b)Pseudomonas-Cetrimideagar c)Mtuberculosis-LJmedium d)Campylobacter-BCYEmedium CorrectAnswer-DAns.is'd'i.e.,Campylobacter-BCYEmedium
290.NottrueaboutHistoplasmacapsulatum ? a)Dimorphicfungus b)MaymimicTB c)Capsulated d)Mostlyasymptomic CorrectAnswer-CAns.is'c'i.e.,CapsulatedHistoplasmacapsulatumAdimorphicfungusNonencapsulatedTheonlymedicallyimportantcapsulatedfungusiscryptococcus.Infectionisacquiredbyinhalationofmicroconidia(smallspores)industcontaminatedwithbirdorbatdropping.Itcausesintracellularinfectionofreticuloendothelialsystem.ClinicalmanifestationsMajorityofpatientsareasymptomatic
291.Schizointarenotseeninperipheral bloodofwhichmalarialparasites? a)Pvivax b)Pfalciparum c)Povale d)Pmalariae CorrectAnswer-BAns.is'b'i.e.,PfalciparumInperipheralsmearoffalciparummalariafollowingformsareseenEarlyringformGametocytesMaturetrophozoitesandschizointarenotfoundinperipheralbloodbecauseschizogonyoccursinsidethecapillaryofinternalorgans(spleen,liverandbonemarrow).
292.SupercarrierofHBVshowsfollowing serummarkers? a)HBsAg b)HbsAg+HBVDNA c)HbsAg+HBeAg+HBVDNA d)Anti-HBsAg+HBVDNA CorrectAnswer-CAns.is'c'i.e.,HbsAg+HBeAg+HBVDNAInHBVinfection,therearetwotypesofcarriers:SuperCarriersHightitreofHBsAg,HBeAg,DNApolymeraseandHBVinthecirculationHighlyinfectiveSimplecarriersLowtitreofHBsAgwithnegativeHBeAg,DNApolymeraseandHBVHavelowinfectivity
293.Coldsterilizationis? a)Sterilizationbynegativetemperature b)Sterilizationbyionizingradiation c)SterilizationbyliquidCO2 d)Sterilizationbynon-ionizingradiation CorrectAnswer-BAns.is'b'i.e.,Sterilizationbyionizingradiation
294.Bestspecimenforanaerobicculture? a)Exudatesfromwound b)Pusaspiratedinvial c)Swabfromwound d)Mid-streamurine CorrectAnswer-BAns.is'b'i.e.,PUSaspiratedinvialIdealspecimensforanaerobicculturesaresamplesofneedleaspiratesandpropertissuespecimens.Anaerobicswabsareusuallydiscouraged.Importantspecimensare:- i. Localabscess:Needleaspirates. ii. Pulmonary:Transtrachealaspirates,lungaspirates,pleuralfluid, protectedbronchialwash. iii. Abdominal:Abdominalabscessaspirate. iv. Urinarytract:Suprapubicbladderaspirate. v. Genitaltract:Culdocentesisspecimen,endometrialswabs. vi. CNS:CSF,Aspirateofabscess. Aspiratedmaterialtheninjectedintooneofthefollowing:? a. Anaerobicswabb. Thioglycollateenrichmentbroth c. Oxygenfreevials Exudates,swabsfromburns,woundandskinabscessesaregenerallyunacceptableforanaerobicculture.Cystsandabscessarecontaminatedwithnormalanaerobicflora.Voidedandcatheterizedurinearecontaminatedwithdistalurethralanaerobesandarethereforeunacceptableforanaerobicculture.
295.Aerobicbloodcultureshouldbe incubatedforhowmanydays,beforediscarding? a)2days b)5days c)10days d)14days CorrectAnswer-DAns.is'd'i.e.,14daysBloodspecimensof5or10mlgenerallyareaddedtobottlescontaining,50or100mlofreagent(medium)toachievea1:10bloodmediumratio.Allbottlesshouldbetransportedtothelaboratoryassoonaspossibleandimmediatelyincubetedat35?2?Cinanuprightposition(Note-Lowerincubationtemperaturemaybepreferredforisolationofsomespecificbacteria,e.g.Listeriagrowswellat20-25?C).Atotalincubationperiodof7daysisgenerallysufficientforroutineisolationprocedure,whichcanbeextendedupto14daysbeforediscardingthosethatdonotshowevidenceofgrowth.
296.Infectiveendocarditisaftertooth extractionisprobablydueto? a)Streptococcusviridans b)Streptococcuspneumoniae c)Streptococcuspyogenes d)Staphylococcusaureus CorrectAnswer-AAns.is'a'i.e.,StreptococcusviridansViridansstreptococciarenormallyresidentinthemouthandupperrespiratorytract.Theycausetransientbacteremiafollowingtoothextractionorotherdentalprocedures;andgetimplantedondamagedorprostheticvalvesorinacongenitallydiseasedheart,andgrowtoformvegetations.Theyareordinarilynonpathogenicbutcanonoccasioncausedisease.Inpersonswithpreexistingcardiaclesions,theymaycausebacterialendocarditis,Str.sanguisbeingmostoftenresponsible.Str.mutansisimportantincausationofdentalcaries.Thetransientviridansstreptococcalbacteremiainducedbyeating,tooth-brushing,flossingandothersourceofminortrauma,togetherwithadherencetobiologicalsurfaces,isthoughttoaccountforthepredilectionoftheseorganismstocauseendocarditis.Viridansstreptococciarealsoisolated,oftenasapartofamixedflora,fromsitesofsinusitis,brainabscessandliverabscess.Viridansstreptococcalbacteremiaoccursrelativelyfrequentlyinneutropenicpatients,particularlyafterbonemarrowtransplantationorhighdosechemotherapyforcancer.Treatmentofvaridansstreptococcalinfectionsinclude:- 1. BacteremiainneutropenicpatientsVancomycin.
2. OtherinfectionPenicillin.
297.Chroniccarrieroftyphoidshedbacillifor ? a)1-3weeksaftercure b)3weeksto3monthsaftercure c)3months-1yearaftercure d)Morethan1yearaftercure CorrectAnswer-DAns.is'd'i.e.,Morethan1yearaftercureCarriersBacillipresistinthegallbladderorkidneyandareeliminatedinthefeces(fecalcarriers)orurine(urinarycarrier),respectively.Thedevelopmentofthecarrierstateismorecommoninwomenandinolderagegroups(over40yrs)Carriersarethemorefrequentsourceofinfectionthancases.Urinarycarriageislessfrequentbutmoredangerousthanintestinalcarrier-ParkPSMUrinarycarrierisgenerallyassociatedwithsomeurinarylesionssuchascalculiorschistosomiasis.PresenceofViantibodyindicatesthecarrierstate.
298.Ovoviviparousparasitewhichis associatedwithautoinfection? a)Ancylostomaduodenale b)Strongyloidesstercoralis c)Enterobiusvermicularis d)Ascaris CorrectAnswer-BAns.is'b'i.e.,StrongyloidesstercoralisAmongthegivenoptions,strongyloidesandenterobiuscancauseautoinfection.Strongyloidesisovoviviparous,whereasenterobiusisoviparous.
299.DoublestrandedRNAvirus? a)Rotavirus b)Measlesvirus c)Mumpsvirus d)Influenzavirus CorrectAnswer-AAns.is'a'i.e.,Rotavirus
300.Earliestgrowthofdiphtheriaisdetecton whichmedia? a)Potassiumtelluritemediawithiron b)McConkey'sagar c)Dorseteggmedium d)Loeffler'sserumslope CorrectAnswer-DAns.is'd'i.e.,Loeffler'sserumslopeDiphtheriabacilligrowonLoeffler'sserumslopeveryrapidlyandcoloniescanbeseenin6-8hours,longbeforeotherbacteriagrow.
301.Bloodagarisanexampleof? a)Enrichedmedia b)Indicatormedia c)Enrichmentmedia d)Selectivemedia CorrectAnswer-AAns.is'a'i.e.,Enrichedmedia
302.Viruscausingoropharyngealcarcinoma ? a)EBV b)HPV c)HHV-8 d)HTLV CorrectAnswer-BAns.is'b'i.e.,HPV
303.Temperaturerequiredforholdingperiod of20minutesinHotairoven- a)160?C b)170?C c)120?C d)130?C CorrectAnswer-BAns.is'b'i.e.,170?C
304.Breakbonefeveriscausedby? a)Yellowfever b)Japaneseencephlitis c)Denguefever d)KFD CorrectAnswer-CAns.is'c'i.e.,DenguefeverBreakbonefever(Saddlebackfever)iscausedbydenguevirus.DenguefeverDenguefeveriscausedbyarboviruses(atleast4serotypeshavebeenrecognized)ItistransmittedbyAedes(Aedesaegyptiisthemainvector).Thereservoirofinfectionisbothmanandmosquito.ThetransmissioncycleisMan-mosquito-manDenguefeveroccursbothepidemicallyandendemically.Epidemicsstartsinrainyseasonandareusuallyexplosive.Aedesmosquitobecomesinfectivebyfeedingonapatientfromthedaybeforeonsettothe5thdayofillness.VariousmanifestationsofDengueinfectionA)Classicaldenguefever? i. Alsoknownasbreakbonefever ii. Incubationperiod2-7days(3-10days-4Park) iii. Onsetissuddenwithchillsandfever.Feverisusuallybetween39?c and40?ctemperaturereturnstonormalafter5-6daysorsubsideonaboutthe3rddayandriseagainafter5-8daysafteronset(saddlebackfever). iv. Rashesappearin80%ofcasesduringremissionorduringsecond febrilephase.Therashlastsfor2hourstoseveraldaysandmaybe
followedbydesquamation.B)DengueHemorrhagicfever(DHF)-Itisasevereformofdenguefevercausedbyinfectionwithmorethanonedenguevirus.Thesevereillnessisthoughttobeduetodoubleinfectionwithmorethanonedenguevirus.Denguehemorrhagicfeverisbelievedtoresultfromreinfectionwithavirusofdifferentserotype(duetoenhancingantibodies)DHFusallyoccursaftersequentialinfectionwithanytwoofthefourserotypesofdenguevirus.Sequenceofinfectionmaybeimportant;serotype1followedbyserotype2ismoredangerousthanserotype4followedbyserotype2.
305.Inpontaicfever,whichantigenisseenin urine? a)Lipopolysaccharide-1 b)Lipopolysaccharide-2 c)Lipopolysaccharide-4 d)Lipopolysaccharide-6 CorrectAnswer-AAns.is'a'i.e.,Lipopolysaccharide-1Legionellaareclassifiedintoserogrouponthebasisofgroupspecificlipopolysaccharide(somaticantigenor'O'antigen).Legionellapneumophilasero-group-1(LP-1)isthemostcommoninfectingorganism.UrinetestdetectLP-1.
306.Sporesofclostridiumperfringensare located? a)Inthemiddleofcells b)Atthepolesofcells c)Betweenmiddleandpoleofcells d)Noneoftheabove CorrectAnswer-CAns.is'c'i.e.,BetweenmiddleandpoleofcellsClostridiumperfringens(C.perfringens)isaspore-forminggram-positivebacteriumthatisfoundinmanyenvironmentalsourcesaswellasintheintestinesofhumansandanimals.C.perfringensiscommonlyfoundonrawmeatandpoultrySporesofclostridiummaybe:? 1. Terminal:Locatedatpoles.2. Central:Locatedinthemiddleofthecells.3. Subterminal:Betweenthemiddleofthecellandpoleofthecells.
307.AgarmediausedforHaemophilus influenza? a)Bloodagar b)Chocolateagar c)Tryptoseagar d)BYCEagar CorrectAnswer-BAns.is'b'i.e.,Chocolateagar
308.Mechanismofactioninpathogenesisof PseudomembranouscolitisbyCIdifficle? a)Duetoinvasiveness b)Duetoendotoxin c)Duetoexotoxin d)DuetoNMblockade CorrectAnswer-CAns.is'c'i.e.,DuetoexotoxinPathogenesisofpseudomembranouscolitisisduetoproductionoftwolargetoxinsbyC.difficile:i)ToxinA(anenterotoxin)IsapotentneutrophilchemoattractantCausesdisruptionofcellcytoskeletonbyglycosylationofGTP-bindingproteinsthatregulatetheactincellcytoskeleton.ii)ToxinB(acytotoxin)Causesdisruptionofcellcytoskeletonbysimilarmechanism.
309.ViruscausingLatentinfection(orLatent periodisshownbywhichvirus)- a)Rubella b)HBV c)Pertussis d)Rotavirus CorrectAnswer-BAns.is'b'i.e.,HBV
310.Trueregardingarbovirusisallexcept? a)KFDistransmittedbyTick b)DenguevirushasoneSerotype c)YellowfeverisnotseeninIndia d)DenguefeveristransmittedbyAedes CorrectAnswer-BAns.is'b'i.e.,DenguevirushasoneSerotypeKFDismainlytransmittedbyHardtick,butsofttickcanalsotransmitthedisease.Denguevirushasfourserotypes.YellowfeverisnotendemicinIndia,itisdistributedinAfricaandSouthAmerica.DenguefeveristransmittedbyAedesmosquito.
311.Bacterianotaffectedbystreptogramins is? a)E.coli b)Staphylococcuaureus c)Legionella d)M.pneumoniae CorrectAnswer-AAns.is'a'i.e.,E.coliStreptograminsareactiveagainstgram-positivecocciandorganismsresponsibleforatypicalpneumonia(e.g.,M.pneumoniae,Legionellaspp.,andChlamydiapneumoniae),butlargelyinactiveagainstgram-negativeorganisms.Theyarebactericidalagainststreptococciandmanystrainsofstaphylococci,butbacteriostaticagainstE.faecium.
312.SmallestVirusis? a)Herpesvirus b)Adenovirus c)Parvovirus d)Poxvirus CorrectAnswer-CAns.is`c'i.e.Parvovirus
313.InfectivityofHBVisindicatedby? a)HBeAg b)HbsAg c)HBVDNA d)AntiHBsAg CorrectAnswer-AAns.is'a'i.e.,HBeAg
314.TrueaboutCMVareallexcept? a)Mostcommoncauseofpost-transpinatationinfection b)Mostcommoncauseoftransplacentalinfection c)Anon-envelopedDNAvirus d)Producesintranuclearinclusions CorrectAnswer-CAns.is'c'i.e.,Anon-envelopedDNAvirusCMVisanenvelopedDNAvirus,belongstoHerpesviridae.
315.NottureaboutElTorbiotypeofvibrio cholerae? a)Lowermortality b)LessSAR c)Lesschancesofsurvivalinenvironment d)VP(+) CorrectAnswer-CAns.is'c'i.e.,Lesschancesofsurvivalinenvironment
316.HSV-2(Herpessimplex)causes? a)Oralulcers b)Genitalulcers c)U.T.I. d)Pharyngitis CorrectAnswer-BAns.is'b'i.e.,Genitalulcer
317.Whichofthefollowingisthemechanism ofactionoftetanospasmin? a)InhibitionofreleaseofGABAandglycine b)InhibitionofAchreleasefromsynapse c)Inhibitionofproteinsynthesis d)Activationofadenylylcyclase CorrectAnswer-AAns.is'a'i.e.,InhibitionofreleaseofGABAandglycinePathogenicityCLtetanihaslittleinvasivepropertyandisconfinedtotheprimarysiteoflodgment.Tetanusresultsfromtheactionofthepotentexotoxinitproduces.
318.Ebolavirusbelongsto? a)Picornaviridae b)Togaviridae c)Flaviviridae d)Filoviridae CorrectAnswer-DAns.is'd'i.e.,Filoviridae
319.Bollingerbodiesareseenin? a)Chickenpox b)Cowpox c)Fowlpox d)Smallpox CorrectAnswer-CAns.is'c'i.e.,Fowlpox
320.AllaretrueregardingJapanese encephalitisexcept? a)Causedbyflavivirus b)Humansaredead-endhosts c)Transmittedbyculex d)Cattlesareamplifierhosts CorrectAnswer-DAns.is'd'i.e.,CattlesareamplifierhostsJapaneseencephalitisCausedbyagroupBarbovirus(flavivirus)ItisaZoonoticdiseaseieinfectingmainlyanimalsandincidentallyman.Insouth,epidemicshaveoccuredinKarnataka,Andhrapredesh,TamilNadu,andKerala.Human,cattle,andhorsesaredead-endhostsasthediseasemanifestsasfatalencephalitis.Pigsactasanamplifyinghostandhaveaveryimportantroleintheepidemiologyofthedisease.Infectioninswineisasymptomatic,exceptinpregnantsows,whenabortionandfetalabnormalitiesarecommonsequelae.ThemostimportantvectorisCulextritaeniorhynchus,whichfeedsoncattleinpreferencetohumans.ThenaturalhostsoftheJapaneseencephalitisvirusarebirds,nothumans.InNovember2011,theJapaneseencephalitisviruswasreportedinCulexbitaeniorhynchusinSouthKorea
321.AllareseenwithPneumocystiscariniin AIDSexcept a)Pneumonia b)Oticpolypoidmass c)Ophthalmicchoroidlesion d)Meningitis CorrectAnswer-DAns.is'i.e.,MeningitisP.jiroveci(formerlyknownasP.carinii)causesinterstitialpneumoniainAIDSpatients.Pneumocystisotomastoiditispresentwithunilateralotalgia,otorrhea,hearinglossandapolypoidmassonotoscopy.Ocularpneumocystisistypicallyrestrictedtochoroidallayerproducingmultiplefocalcircumscribedcreamytoyellow-whitelesions
322.Antibioticsensitivitytestingcanbedone usingallexcept a)Etest b)Kirby-Bauermethod c)Cultureagarmethod d)Brothdilutionmethod CorrectAnswer-CAns.is'c'i.e.,CultureagarmethodTestsusedforantimicrobialsensitivityare: 1. Discsusceptibilitytest(mostcommonlyused)2. Brothdilutionsusceptibilitytest3. Kirby-Bauerdiscdiffusionmethod4. E-test(Epsilonietertest)
323.TypeEadversereactionis a)Toxicity b)Augmentedeffect c)Teratogenesis d)Withdrawalreaction CorrectAnswer-DAns.is'd'i.e.,WithdrawalreactionTypeA(Augmented)reactionExcessofnormal,predictable,doserelatedpharmacodynamiceffect.Mayoccurineveryoneeg-Posturalhypotension,hypoglycemiaTypeB(Bizzare)reactionDuetounusualattributesofthepatientinteractionwiththedrug.NotdoserelatedNotapartofnormalpharmacologicaleffectofadrug.Occursonlyinsomepeople.eg-Idiosyncracyanddrugallergy.TypeC(chronic)reactionDuetolongtermexposureeg;Analgesicnephropathy,dyskinesiabylevodopa,immunosuppressionbycorticosteroids.TypeD(Delayed)effectseg;Carcinogenesisorteratogenesis.TypeE(Endingofuse)reaction3eg;withdrawlreactionswithclonidine.
324.Treponemapallidumwasdiscoveredby ? a)RobertKoch b)Twort c)SchaudinnandHoffman d)Ellerman CorrectAnswer-CAns.is'c'i.e.,SchaudinnandHoffman Bacteria Discoveredby Leprabacillus(M.Leprae) Hansen(1874) Gonococcus Neisser(1879) Staphylococcus Ogston(1881) Diphtheriabacillus(C.Diphtheria) Loeffler(1884) Tetanusbacillus(C.Tetani) Nicolaier(1884) Pneumococcus Fraenkel(1886) CausativeorganismforMaltafever Bruce(1887) (Brucella) SchaudinnandHoffmann Spirocheteofsyphilis(Tpallidum) (1905)
325.Lactosefermentationisseenin? a)Bloodagar b)Chocolateagar c)MacConkeyagar d)LJmedium CorrectAnswer-CAns.is'c'i.e.,MacConkeyagarCultureondifferentialmediathatcontainspecialdyesandcarbohydratesdistinguisheslactose-fermenting(colored)fromnon-lactose-fermenting(non-pigmented)coloniesandmayallowrapidpresumptiveidentificationofentericbacteria.Suchmedia,usedtoseelactosefermentation,are:? 1. Eosine-methyleneblue(EMB)2. MacConkey'sagar3. Deoxycholateagar
326.Majorimmunoglobulinsecretedby intestine? a)IgG b)IgM c)IgA d)IgD CorrectAnswer-CAns.is'c'i.e.,IgAItisthesecondmostabundantantibody(afterIgG)'Itismajorimmunoglobulininclostrum,saliva,tears,respiratoryandgastrointestinalsecretions.
327.Falseaboutvirusesis? a)Ribosomesabsent b)Mitochondriaabsent c)Motilityabsent d)Nucleicacidabsent CorrectAnswer-DAns.is'd'i.e.,NucleicacidabsentVirusescontainnucleicacid,eitherRNAorDNA.PropertiesofvirusesVirusesareobligateintracellularparasites.Theylackenzymesnecessaryforproteinandnucleicacidsynthesisandaredependentforreplicationonthesyntheticmachineryofhostcellsso,theycannotgrowincellfreeculturemedia.Theydonothavecellularorganization.Theyareunaffectedbyantibacterialantibiotics.Theycontainonlyonetypeofnucleicacid,eitherRNAorDNA,neverboth.Theymultiplybyacomplexprocessandnotbybinaryfission.Theextracellularinfectionsvirusparticleiscalledthevirion.oWithfewexceptions,virusesareveryheatlabile.
328.Arrangementoflensfromeyetosource oflight,inlightmicroscope? a)Ocularlens:Subjectivelens:Condensorlens b)Subjectivelens:Ocularlens:Condensorlen c)Condensorlens:Sujectivelens:Ocularlens d)Subjecivelens:Condensorlens:Ocularlens CorrectAnswer-AAns.is'a'i.e.,Ocularlens:Subjectivelens:Condensorlens
329.Numbersofvariableregionsoneach lightandheavychainofanantibody? a)1 b)2 c)3 d)4 CorrectAnswer-AAns.is'a'i.e.,1
330.Hybridomatechniqueisusedtoobtain? a)Specificantigen b)Complement c)Specificantibody d)Interleukins CorrectAnswer-CAns.is'c'i.e.,SpecificantibodyHybridomasarecellsthathavebeenengineeredtoproduceaspecificantibodyinhugenumbers.HybridomasHybridomasarecellsthathavebeenengineeredtoproduceaspecificantibodyinhugenumbersToachievethis,qualitiesoftwotypesofcellshavetobecombinedtogetheri.e.CellswhichcanproducelargeamountofpureantibodyandCellswhichhavetheabilitytogrowcontinually.Thesetwotypesofcellsarethenfusedtogethertoformhybridoma.ProcedureThepureantibodysecretingcellsareproducedbyinjectingspecificantigeninamouseandobtainingtheantigenspecificplasmacells(antibodyproducingcell)fromthemouse'sspleen.Cellwhichcangrowindefinitelyinculturearemyelomacells(cancerouscells).Thesetwocelllinesarefusedtogether.Thehybridcellwhichisthusproducedcanbeclonedtoproducelargenumberofidenticaldaughterclones.Thesedaughterclonecellsthenproduceantibodies.Sincetheseantibodiescomefromonlyonetypeofcell(hybridomacell)theyare
calledmonoclonalantibodies.HAT(hypoxanthine,Aminopterinandthymidine)mediumisusedforpreparationofmonoclonalantibodiesbecauseitallowsonlyfusedhybridomacellstogrow.Itdoesnotallowtheunfusedmyelomaandunfusedantibodycellstogrow.SoHATmediumisaselectivemediumwhichallows(whichallowselectivegrowthoffusedhybridoma)Howdoesthishappen?Beforewemoveonwiththediscussion,rememberthesefewpointsaboutpurinesynthesis.Purinesynthesisisessentialforthesurvivalofcells.Purinecanbesynthesizedintwowayi.e.Denovosynthesis(dihydrofolatereductaseenzymeisrequiredforthispathway).Salvagepathway(anenzymehypoxanthine-guaninephosphoribosyltransferaseisrequiredforsalvagepathways)MyelomacellslackHGPRTaseenzymethereforetheycannotsynthesizepurinebysalvagepathways.oAntibodycellshaveHGPRTaseenzymesotheycanusethesalvagepathways.AminopterininhibitsdihydrofolatereductaseanenzymeusedindenovosynthesisofpurineWhentwocelllinesi.e.antibodyproducingcellandmyelomacellsaregrowninHATmediumonlythefusedhybridomacellssurvive.MyelomacellsdiebecausetheylacktheenzymeHGPRTasesotheycannotusethesalvagepathwaysforpurinesynthesis.Theyalsocannotusede-novopathway,becauseAminopterinpresentintheHATmediuminhibitsdihydrofolatereductase(anenzymeessentialfordenovosynthesisofpurine).Theunfusedantibodyproducingcellsdieastheycannotgrowindefinitelybecauseoftheirlimitedlifespan.OnlyfusedhybridomacellsgrowindefinitelybecausetheantibodycellpartnersuppliesHGPRTaseandthemyelomapartnergivesitimmortality.(asitisacancercell)
331.WhichisnotaDNAvirus? a)Parvovirus b)Papovavirus c)Poxvirus d)Rhabdovirus CorrectAnswer-DAns.is'd'i.e.,Rhabdovirus
332.Allaresporicidalagentsexcept? a)Formaldehyde b)Glutaraldehyde c)Ethyleneoxide d)Isopropylalcohol CorrectAnswer-DAns.is'd'i.e.,IsopropylalcoholSporicidalagentsBacterialsporesconstitutesomeofthemostresistantformsoflife.Bynaturebacterialsporesareresistanttoextremephysical,chemicalandthermalconditionsandaresecondonlytoprionsintheirresistancetodisinfection.Theyareresistanttomostofthedisinfectants.Onlyafewagentsareeffectiveagainstthem.Sporicidalagentsare-GlutaraldehydeFormaldehydeHalogens 1. Iodinecompounds-,Iodine,Iodophors2. ChlorinecompoundsSodiumhypochlorite,chlorinetablets EthyleneoxidePeroxygenshydrogenperoxide,peraceticacid.BetapropiolactoneOzoneFollowingcompondsareusuallysporostatic,butmaybecomesporicidalathighertemperature?PhenolsCresols
Organomercurycompounds(Sodiumthioglycolate)Chlorhexidine(Hibitane)
333.Inbloodculturetheratioofbloodto reagentis? a)1:5 b)1:20 c)1:10 d)1:100 CorrectAnswer-CAns.is'c'i.e.,1:10
334.SabinfeldmanDyetestisusedto demonstrateinfectionwith? a)Filaria b)Toxoplasma c)Histoplasma d)Ascaris CorrectAnswer-BAns.is?b'i.e.,ToxoplasmaThepolyclonalIgGantibodiesevokedbyinfectionareparasiticidalinvitrointhepresenceofserumcomplementandarethebasisfortheSabin-Feldmandyetest.LaboratorydiagnosisoftoxoplasmosisLaboratorydiagnosiscanbemadeby 1. Microscopicdemonstrationoftheparasite2. Isolationoftheparasitebyanimalinoculationortissueculture.3. Polymerasechainreaction4. Serology ThemostcommonmethodoflaboratorydiagnosisPersonsshouldinitiallybetestedforthepresenceofToxoplasmaspecificIgGantibodiestodeterminetheirimmunestatus.ApositiveIgGtitreindicatesinfectionwiththeorganismatsometime(recentorpast).ThenanIgGpositivepersonshouldhaveanIgMtest.Anegativetestessentiallyexcludesrecentinfection.However,apositiveIgMtestdoesnotalwaysmeanarecentinfectionbecausetoxoplasmaspecificIgMantibodiesmaypersistformonthstoyearfollowingprimaryinfection.Therefore:?NegativeIgMwithpositiveIgGalwaysmeansapastinfection.
PositiveIgMwithpositiveIgGindicatespossibilityofrecentinfection,butnotwith100%surety.Itmayormaynotberecentinfection.Todifferentiatebetweenrecentandpastinfection,IgGaviditytestisused.ItisworthnotingherethatathirdsituationisalsopossiblewhenIgMtestispositivebutIgGtestisnegative.Inthissituationasecondsampleshouldbetakenafter2-4weeksandshouldbetested:?IfthesecondsampleispositiveforIgGandIgM,itindicatesthatthefirstsamplewastakenearlyinthediseasewhenIgGwasnotyetdeveloped.IfthesecondsampleisstillnegativeforIgGwithpositiveIgM,itindicatesfalsepositiveIgMtest. TestsforIgGantibodies TestsforIgMantibodies IgGELISA/EIA IgMindirectflourscentantibody Sabin-Fieldmandyetest test(IgMIFA) IgGindirectflourscent DoublesandwichELISA antibodytest(IgGIFA) IgMcaptureEIA Diffemtialagglutination( Immunosorbantagglutination AC/HS) assay(ISAGA) Aviditytest
335.Culturemediumusedforentamoeba histolytica? a)Bloodagar b)Philip'smedium c)CLEDmedium d)Trypticaseserum CorrectAnswer-BAns.is'b'i.e.,Philip'smediumCulturesmediausedforcultivationofE.histolyticaare:-1.BoeckandDrbohlav'smedium2.Philip'smedium3.ShafferandFrye'smedium4.Jonesmedium5.Balamuth'smedium6.Diamond'smedium
336.Ascosporeis? a)Asexualspore b)Sexualspore c)Conidia d)Noneoftheabove CorrectAnswer-BAns.is'b'i.e.,SexualsporeFungalsporesMostfungireproducethroughthegenerationofsporesFungiproducesporesbytwomethods?SexualreproductionSexualsporesAsexualreproductionAsexualspores
337.Mostcommonstaphylococcalphage straincausinghospitalinfection? a)80/81 b)79/80 c)3A/3C d)69/70 CorrectAnswer-AAns.is'a'i.e.,80/81HospitalstrainsofstaphylococcusaureusCertainstrainsofstaphylococcusarethecommoncauseofpost-operativewoundinfectionsandotherinfectionsinthehospitalenvironment.Thesestrainsareknownashospitalstrains.Thehospitalstrainsshowthefollowingcharacteristics: 1. Theyareresistanttopenicillin,methicillinandotherroutinelyused antibiotics. 2. Theybelongtocertainbacteriophagetypes.3. Someofthestrains(egphagetype80/81)areknowntocause hospitalinfectionsthroughouttheworld.Suchstrainsarecalledasepidemicstrains.
338.Allofthesterilizationmethodsare properlymatchedexcept? a)Catgutsuture-Radiation b)Culturemedia-Autoclaving c)Bronchoscope-Autoclaving d)Glassware&syringes-Hotairove CorrectAnswer-CAns.is'c'i.e.,Bronchoscope-Autoclaving
339.Endoscopetubeissterilizedby? a)Glutaraldehyde b)Formalin c)Autoclaving d)Boiling CorrectAnswer-AAns.is'a'i.e.,Glutaraldehyde2%Glutaraldehyde(cidex)ismostoftenusedforequipmentsuchasendoscopethatcannotbesterilizedordisinfectedbyheat.
340.Allaretrueregardingresistanceof penicillininstaphylococcusaureus,except? a)Penicillinaseproductionistransmittedbytransduction b)MethicillinresistanceisduetochangeinPBP c)HospitalstrainsmostlyproducetypeDpenicillinase d)Penicillinaseproductionisplasmidmediated CorrectAnswer-CAns.is'c'i.e.,HospitalstrainsmostlyproducetypeDpenicillinaseResistancetoantibioticsaPenicillinresistanceisofthreetypes?1.Productionofbeta-lactamase(penicillinase)Itinactivatespenicillinbysplittingbeta-lactamringItsproductioniscontrolledbyplasmid.Plasmidistransmittedbytransduction(mainly)orconjugation.PenicillinaseisaninducibleenzymeAsaresultofthewidespreaddisseminationofplasmidscontainingpenicillinase,lessthan5%strainsofstaph.remainsusceptibletopenicillin.Staphylococciproducefourtypesofpenicillinases,AtoD.Hospitalstrainsusuallyformtype'A'penicillinase.2.Changesinbacterialsurfacereceptorsbylackorinaccessibilityofcertainpenicillin-bindingproteins(PBPs)intheorganism.Methicillin-resistantismainlyduetothismechanismandisindependentofbeta-lactamaseproduction.ItisduetotheproductionofPBP2a.Thischange(inbacterialsurfacereceptors)isnormally
chromosomal.TheresistancegeneismecAgenewhichisapartofalargemobilegeneticelement-staphylococcalcassettechromosome(SCCmec).ThisgeneticmaterialhasbeentransferredtoStaph.aureusfromS.seiuri.3.Developmentoftolerancetopenicillin,bywhichthebacteriumisonlyinhibitedbutnotkilled
341.Whichofthefollowingisnotcapsulated ? a)Pneumococcus b)Cryptococcus c)Meningococcus d)Proteus CorrectAnswer-DAns.is'd'i.e.,ProteusCapsuleManybacteriasecreteaviscidmaterialaroundthecellsurface.Whenthisisorganizedintoasharplydefinedstructure,itisknownascapsule.Capsulesareprotectiveandprotectthebacteriafromphagocytosisandfromlyticenzymes.Somebacterialoosetheircapsulesonrepeatedsubcultures. CapsulatedorganismsPneumococcus Yersinia Bacillusanthrax V.parahemolyticus Bordetella H.influenzaeFreshstrainsofstaphylococci,streptococci Meningococci and'Ecoli. Cl.perfringensandCl. Bacteroides butyric=Klebsiella Cryptococcus.
342.Allaretrueregardinginterleukin-1 except? a)Primarysourceismonocyte-macrophagesystem b)Endogenouspyrogens c)InhibitIL-2productionbyT-cells d)Allaretrue CorrectAnswer-CAns.is'c'i.e.,InhibitIL-2productionbyT-cellsInterleukin-1Alsoknownasleucocyteactivatingfactor(LAF)orBcellactivatingfactor(BAF).Principallysecretedbymacrophagesandmonocytes;andepithelialcells.OthersourcesareBlymphocytes,fibroblastsandendothelialcells.Immunologicaleffects-ActivationofTcellsfortheproductionofIL-2.BcellproliferationandantibodysynthesisNeutrophilchemotaxisandincreasedPMNreleasefrombonemarrow.Increasesbodytemperature(importantendogenouspyrogen).BonemarrowcellproliferationInductionofacutephaseprotein.
343.Whichofthefollowingisasuperantigen ? a)Choleratoxin b)Diphtheriatoxin c)TSST d)Vero-cytoxin CorrectAnswer-CAns.is'c'i.e.,TSSTSuperantigensCertainspeciesofinfectiousmicroorganismsproducepowerful,immunostimulatoryanddiseasecausingtoxinscalledsuperantigen,socalledbecauseoftheirabilitytopolyclonallyactivelargefraction(upto20%)ofTcellpopulation.SuperantigensarepotentactivatorsofT-lymphocytes.SuperantigensstimulateverylargenumbersofTcells,withoutrelationtotheirepitopespecificity.ThisleadstoanexcessiveanddysregulatedimmuneresponsewithreleaseofcytokinesIL-1,IL-2,TNF-aandIF-y.ConventionalantigensbindtoMHCclassIorIImoleculesinthegrooveofthecc13dimer(Tcellreceptor).Incontrast,superantigenbinddirectlytothelateralportionofTCR13chainandMHCclassII13chain,andstimulateTcellssolelyon713genesegmentutilizedindependentoftheD,Jandya-sequencespresentTf3restrictedTcellmitogens.Superantigensarecapableofactivatingupto20%oftheperipheralT-cellpool,whereasconventionalantigensactivate<Iin10,000. Examplesofsuperantigen Certainnonhuman Staphylococcaltoxicshocksyndrome retroviralproteins.
Staphylococcaltoxicshocksyndrome retroviralproteins. toxin Yersinia Staphylococcalenterotoxins pseudotuberculosis Staphylococcalexfoliative(erythrogenic) Mycoplasmaarthritis. toxin Mousemammarytumor Streptococcaltoxicshocksyndrometoxin virus.
344.Thomsenfriedensreichphenomenonis? a)RedcellsinfectionbyCMV b)Redcellagglutinationbyallbloodgroupsera c)Hemolysisoftransfusedblood d)DuetoBantigen CorrectAnswer-BAns.is'b'i.e.,RedcellagglutinationbyallbloodgroupseraThomsen-FreidenreichPhenomenonRedcellsuspensionscontaminatedwithcertainbacteria,e.g.pseudomonasaeruginosa,becomeagglutinablebyallbloodgroupseraandevenbynormalhumansera.ThisisknownasThomsenFriedenreichphenomenonandisduetounmaskingofahiddenantigennormallypresentonallhumanerythryocytes,i.e.T-antigen.Anti-Tagglutininsarenormallypresentinhumansera.Suchpanagglutinabilityofredcellshasoccasionallybeenobservedinpersonssufferingfromsystemicbacterialinfections.
345.MostcommonorganismcausingURTIin adult? a)Hinfluenza b)Stapaureus c)Streptopneumonia d)Streptococcuspyogenes CorrectAnswer-DAns.is'd'i.e.,StreptococcuspyogenesMostcommoncauseofupperrespiratorytractinfectionisviralinfection.Rhinovirusisthemostcommoncause.Amongthebacteria,groupAbeta-hemolyticstreptococci(streptococcuspyogenes)isthemostcommoncause.Andmostcommontypeofinfectionispharyngitis.
346.Streetrabiesviruscause? a)Naturalrabies b)Loboratorypassageinrabbit c)Fatalencephalitisin6days d)Negribodiesnotseen CorrectAnswer-AAns.is'a'i.e.,Naturalrabies
347.AllaretrueaboutHelminths,except? a)AlimentarycanaliscompleteinNematodes b)Bodycavityispresentintrematodes c)Nematodeshaveseparatesexes d)AlimentarycanalisPresentbutincomplete CorrectAnswer-BAns.is'i.e.,B-Bodycavityispresentintrematodes 1. OptionbisincorrectBodycavityispresentintrematodes,Itis ActuallyAbsent. 2. Optiondiscorrect-->alimentarycanalispresentintrematodes,itis incompletewithnoanus.Thus,optionbisthebestanswerhere.TableshowingthedifferencesbetweenCestodes,TrematodesandNematodes Cestode Trematode Nematode Shape Tape-like; Leaf-like; Elongated, segmented unsegmented cylindrical; unsegmented Sexes Notseparate, Notseparate Separate i.e., (Monoecious), (diecious) hermaphrodite except (monoecious) Schistosomes whichare diecious Nosuckers,no hooks Suckers,often Suckers,no Well-developed "Head"End withhooks hooks buccal capsuleinsome
capsuleinsome species Presentbut Presentand Alimentarycanal Absent incomplete/no completeanus anus present Bodycavity Absent Absent Present
348.Whichofthefollowingamoebaedoes nothaveneuropathogeniceffect? a)Naegleria b)Acanthamoeba c)Dientamoeba d)Balamuthia CorrectAnswer-CAns.is'c'i.e.,DientamoebaNeuropathogenicamoebaeareNaegleriaFowleriCausesprimaryamebicmeningoencephalitis.AcanthamoebacausesgranulomatousamebicencephalitisBalamuthiamandrillariscausesamebicmeningoencephalitis.
349.Allofthefollowingareimportant mechanismsofgenetransferinbacteria,except? a)Lateralgenetransfer b)Conjugation c)Verticalgenetransfer d)Horizontalgenetransfer CorrectAnswer-CAns.is'c'i.e.,VerticalgenetransferGenetransferGenetransferreferstotheprocessofgeneticmaterial(e.g.DNA)beingsentandreceivedamongtwoorganisms-*Donorsendsandrecipientreceivesthegeneticmaterial.Therearetwoprocessesofgenetransfer:?1.Horizontalgenetransfer(HGT)orlateralgenetransferHorizontalgenetransferistheprocessbywhichgeneticmaterialispassedbetweentwodifferentorganism,i.e.organismofdifferentspecies.Therecipientisnottheoffspringofdonor.Themostimportantexampleisgenetransferbetweenthebacteria.Theprocessesofhorizontalgenetransferinbacteriaare:- 1. Transduction2. Transformation3. Conjugation 2.VerticalgenetransferVerticalgenetransferistheprocessoftransferringgeneticmaterialtoorganismofsamespecies,i.e.donorrecievesgeneticmaterial
fromitsancestor,e.g.itsparentoraspeciesfromwhichitevolved.Therefore,thedonorwillhavethesamegeneralmakeupastheparents.Verticalgenetransferis"amixoftwoparents",i.e.whentwoorganismsmate,theirgenesareverticallytransferedtotheirspawn.Thisprocessisnotimportantinbacteria.
350.AllaretrueregardingdevelopmentofT- cells,except? a)T-cellsareformedinbonemarrow b)MaturationofT-cellstakeplaceinthymus c)T-cellarelocatedinmantlelayerofspleen d)Inlymphnodes,T-cellsarefoundinparacorticalarea CorrectAnswer-CAns.is'c'i.e.,T-cellarelocatedinmantlelayerofspleenTcellsoriginandmaturationTcellsoriginateinthebonemarrow,fetalliverandyolksacandmatureinthymus.Tcellprecursorsfromtheyolksac,fetalliverandbonemarrowmigratetothethymusduringembryonicandpostnatallife.MaturityofT-cellstakesplaceinthethymus.AftermaturityT-lymphocytesareselectivelyseededintocertainsitesoftheperipherallymphatictissues,knownas"thymus-dependentregions".Thymusdependentregionsare-Paracorticalareaoflymphnode.Whitepulpofthespleen,aroundthecentralarteriole.Afterneonatalthymectomy,thesourceofmatureTcells(thymus)willbeabsent.AsaresultthethymusdependentregionsofperipherallymphoidorganswillbedepletedofTcells.B-celloriginandmaturationIncontrasttoTcells(whichoriginateinbonemarrowandmatureinthymus),originaswellasmaturationofB-cellstakesplaceinthebonemarrow.Aftermaturation,B-cellsmigratetoperipheralT-cellindependent
lymphoidregions.T-cellindependentregionsare? 1. Perifollicularregionandmantlelayerofspleen.2. Corticalfollicles,germinalcentresandmedullarycordsoflymph node.
351.Theonlyovoviviporousparasite? a)Ascaris b)Strongyloides c)Enterobius d)Ancylostome CorrectAnswer-BAns.is'b'i.e.,StrongyloidesStrongyloidesstercoralisisahumanpathogenicparasiticroundwormcausingthediseasestrongyloidiasis.Ovo-viviparous(layeggswhichhatchimmediately)Strongyloidesstercoralis,aovo-viviparousintestinalnematodecausesstrongyloidiasis,whichismanifestedbyskinrashes,eosinophilia,andabdominalabdominalpain.Infectionusuallyusuallyresultsinasymptomaticchronicdiseaseofthegut,whichcanremainundetectedfordecades.
352.Allorganismsshowsbipolarstaining except? a)Calymmatobactergranulomati b)Y.pestis c)Pseudomonasmallei d)H.influenzae CorrectAnswer-DAns.is'd'i.e.,H.influenzaeSafetypinappearance(Bipolarstaining) 1. yersiniapestis2. Vibrioparahemolyticus3. Burkholderiamallei4. Burkholderiapseduomallei5. Klebsiellagranulomatis
353.Draughtsman(ConcentricRings)on cultureareproducedby? a)Yersinapestis b)H.ducreyi c)B.pertusi d)Pneumococi CorrectAnswer-DAns.is'd'i.e.,PneumococciDuetoalphahemolysis,coloniesofpneumococciresemblecoloniesofStr.viridans.Butonfurtherincubation,thecoloniesofpneumococcibecomeflatwithraisededgesandcentralumbonation,sothatconcentricringsareseenonthesurfacewhenviewedfromabove-->draughtsmanorCarromcoinappearance.
354.Causativeagentformelioidosisis? a)Pseudomonaspseudomallei b)Pseudomonasaeruginosa c)Pseudomonascepacia d)Pseudomonasmallei CorrectAnswer-AAns.is'a'i.e.,PseudomonaspseudomalleiBurkholderiapseudomalleiisarecognizedbiothreatagentandthecausativeagentofmelioidosis.ThisGram-negativebacteriumexistsasasoilsaprophyteinmelioidosis-endemicareasoftheworldandaccountsfor20%ofcommunity-acquiredsepticaemiainnortheasternThailandwherehalfofthoseaffecteddie.Melioidosiscanbecontractedviacutaneousinoculation,inhalation,oringestion,andcanpresentwithextremelyvariedsymptoms,thesevaguesymptomsanddiverseclinicalpresentations,alongwithculture-baseddiagnosticanomalies,makeitdifficulttoproperlydiagnoseinclinicalsettings.NovaccinesagainstB.pseudomalleiarecurrentlyavailable,makingrapiddetectionandspecificantibiotictreatmentcrucialforfavorableoutcomesininfectedhumans
355.Specificreasontodisallowthesample forculture? a)Samplebroughtwithin2hrofcollection b)Samplebroughtinsterileplasticcontainer c)Samplebroughtinformalin d)Sampleobtainedaftercleaningthecollectionsite CorrectAnswer-CAns.is'c'i.e.,SamplebroughtinformalinGuidelinesforproperspecimencollectionCollectspecimenbeforeadministeringantibioticsorantiviralswhenpossible.Collectspecimenwithaslittleskincontaminationaspossibletoensurethatthesamplecollectedrepresentstheinfectedsite.Utilizeappropriatecollectiondevices.Usesterileequipmentandaseptictechniquetocollectspecimenstopreventintroductionofmicroorganismsduringinvasiveprocedures.Clearlylabelthespecimencontainerwithpatient'sname,hospitalnumberorotheridentifyingnumber(i.e.birthdate,requisitionnumber),dateandtimeofcollection.Collectanadequateamountofspecimen.Inadequateamountsofspecimenmayyieldfalse-negativeresults.Ifaspecimeniscollectedthroughintactskin,cleansetheskinfirst.Forexample,use70%alcoholfollowedbyiodinesolution(1to2%tinctureofiodineor10%solutionofpovidoneiodine).Collectfluidspecimensinsturdy,sterile,screwcap,leakproofcontainerswithlidsthatdonotcreateanaerosolwhenopened.Specimensobtainedbyaphysicianusingneedleaspirationshouldbetransferredtoasteriletubeoranaerobictransportvialpriorto
transportofthespecimentothelaboratory.Ifthereislittlematerialinthesyringe,thephysicianshoulddrawasmallamountofsterilenonbacteriostatic0.85%NaC1throughthesyringeandthentransferthespecimentoasteriletube.Alternatively,andONLYifthespecimenwillbecompromisedbytransferringitfromthesyringe,asmallamountofsterile0.85%NaC1maybedrawnintothesyringepriortoremovaloftheneedle.DONOTTRANSPORTSYRINGESWITHNEEDLESATTACHEDAND/ORRECAPPED.AttachsyringecapONLYifnecessary.Thephysicianshoulduseaprotectivedevicewhileremovingtheneedletoavoidinjuryandshouldcapthesyringewithasterilecappriortotransportingittothelaboratory.AnyMicorbiologyandVirologyspecimenscollectedinformalinareUNACCEPTABLEforculture.
356.Glassvesselsandsyringesarebest sterilisedby- a)Hotairoven b)Autoclaving c)Irradiation d)Ethylenedioxide CorrectAnswer-AAns.is`a'i.e.,HotairovenHotairovenHotairovenareelectricaldevicesusedinsterilization.Theovenusesdryheattosterilizearticles.HotairovenisusedforGlasswareSwabsLiquidparaffinFatandgreaseAllglasssyringeForceps,scissors,scalpelsDustingpowder
357.Sporesofbacteriaaredestroyedby a)Alcohol b)Lysol c)Halogen d)Ionizingradiation CorrectAnswer-CAns.is'c'i.e.,HalogenAmongstthegivenoptions,onlyhalogenshavesporicidalproperty
358.Cellwalldeficientorganismsare a)Chlamydia b)Mycoplasma c)Streptococcus d)Anaerobes CorrectAnswer-BAns.is'b'i.e.,MycoplasmaMycoplasmaSmallestfreelivingorganism,areprokaryotesLackcellwall,areboundedbyatriplelayeredunitmembranethatcontainssterol(thereforemycoplasmasrequiresterolforgrowth).Theirlackofcellwallisassociatedwithcellularpleomorphismandresistancetocellwall-activeantimicrobialagents,suchaspenicillinsandcephalosporins(13-lactamdrugs).Multiplicationisbybinaryfission.Uniqueamongprokaryotesistherequirmentofmostmycoplasmasforcholesterolandrelatedsterols.
359.Vaccineisavailableagainstwhichtype ofmeningococcus? a)TypeA b)TypeB c)TypeAandC d)TypeBandD CorrectAnswer-CAns.is'c'i.e.,TypeAandCVaccineisaavailableagainsttypeA,typeC,typeYandtypeW-135meningococci.
360."Citronbodies"boatorleafshaped pleomorphicorganisminanexudateis a)Cl.welchii b)Cl.edematiens c)Cl.septicum d)Cl.tetani CorrectAnswer-CAns.is'c'i.e.,ClostridiumsepticumCitronbodiesandboatorleafshapedpleomorphicbacilliwithirregularstainingsuggestCLsepticum".ClostridiumClostridialspeciesare:GrampositiveAnaerobic(obligateanaerobe)SporeformingBacilliMotilebyperitrichateflagellaexceptCperfringensandC.tetanitypeIVwhicharenonmotile.NoncapsulatedexceptC.perfringensandC.butyricumwhicharecapsulatedPathogenesisisduetoexotoxinnotendotoxin.Clostridiumbotulinumcausesbotulismnotgasgangrene.Gasgangreneiscausedby:C.perfringens(80%)CnovyiC.septicumC.histolyticum
361.Swarminggrowthoncultureis characteristicofwhichGrampositiveorganism? a)Clostridiumwelchi b)Clostridiumtetani c)Bacilluscereus d)Proteusmirabilis CorrectAnswer-BAns.is'b'i.e.,ClostridiumtetaniSwarminggrowthSwarminggrowthisduetothemotilityofbacteria.Inyoungculture,discretecoloniesareseenbutthereafteractivelymotilecellsspreadonthesurfaceoftheplateinsuccessivewavestoformathinfilmylayerinconcentriccircles.Gram-positiveorganismshowingswarminggrowthC.tetaniandBacilluscereusGram-negativeorganismshowingswarminggrowthProteusmirabilisandProteusvulgaris
362.MostcommongeneticplayinNeisseria infectionis a)Malegender b)HLAb27 c)Complementdeficiency d)IgAdeficiency CorrectAnswer-CAns.is'c'i.e.,ComplementdeficiencyItisanessentialcomponentoftheinnateimmunedefenceagainstinfectionbyNeisseria(N.meningitidesandN.gonorrhoea).Peoplewholackorhaveadeficiencyincomplement-mediatedbactericidalactivityaremostsusceptibletoNeisseriadiseases.Terminalcomplementcomponent(C5throughC9)deficienciesanddeficienciesofthealternativepathway(Properdin,C3,FactorD)haveastrongeffectonsusceptibilityto,aswellastheseverityof,neisserialinfections. 1. Deficiencyofterminalcomplement(C,-C9)component:-Deficiency ofoneoftheterminalcomponentsthatcomposemembraneattackcomplex(MAC)predisposespatientstoinfectionwithNeisseriameningitidesorNeisseriagonorrhoeae.However,N.meningitidesinfectionismorecommon. 2. Deficienciesoftheterminalpathway:-Deficienciesincomponentsof thealternativepathway,namelyproperdin,C3andfactorD,havebeenassociatedwithincreasedsusceptibility,almostexclusively,tomeningococcalinfection(amongstNeisseria).
363.Heatlabileimmunoglobulin a)IgA b)IgG c)IgE d)IgM CorrectAnswer-CAns.is'c'i.e.,IgEOnlyheatlabileIgInactivatedat56degreesCinonehour.
364.WhichisthelongestDNAofhepatitisB virus? a)Pgene b)Xgene c)Sgene d)Cgene CorrectAnswer-AAns.is'a'i.e.,Pgene
365.Bacterialcountindoudenum a)105pergram b)10'pergram c)1010pergram d)10'2pergram CorrectAnswer-AAns.is'a'i.e.,105pergramInGITofanadult:Duodenum-4103-106bacteriapergram.Jejunumandproximalileum10'-108bacteriapergramLowerileumandcecum108-1010bacteriapergramColonandrectum10"-1012bacteriapergramColonandrectumhavemaximumnumberofbacteriaandmostofthem(96-99%)areanaerobes:AnaerobicstreptococciClostridiaAnaerobiclactobacilliBacteroides
366.CapacityofproducingIgGstartsatwhat age a)6months b)1year c)2years d)3years CorrectAnswer-AAns.is'a'i.e.,6monthsImmediatelyafterbirth,thenewbornhashighlevelofIgGantibodiesinbloodstream.Buttheseantibodiesarepassivelytransferredtothebabyfrommother(i.e.,maternalantibodies).Duringnextfewmonths,thematernalIgGantibodiessteadilydecrease.Whenhealthybabyisabout2-3monthsold,theimmunesystemstartsproducingitsownIgGantibodies.Oncehealthybabiesreachsixmonthsofage,theirIgGproductinreachesatnormallevel.NoteIgMantibodiesproductionstartsbeforebirthonly(3-6monthsbefore),butatverylowlevel.
367.Job'ssyndromeisthefollowingtypeof immunonodeficiencydisease a)Humoralimmunodeficiency b)Cellularimmunodeficiency c)Disorderofcomplement d)Disorderofphagocytosis CorrectAnswer-DAns.is'd'i.e.,DisorderofphagocytosisJobssyndromeisdefectinphagocyticfunction.Itischaracterizedbycoldstaphylococcalabscess,atopiceczema,otitismedia;serumimmunoglobulinsarenormalexceptIgEthatiselevated
368.Prionsarebestkilledby a)Autoclavingat134?C b)5%formaline c)Sodiumhypochloride d)Noneofthese CorrectAnswer-AAns.is'A'i.e.,Autoclavingat134?CIncinerationistheonlywayofdisinfectingprion-contaminatedmaterialsortissues.Boilingorirradiationdoesnotaffectandevenroutineautoclaving(at121?C)isnotreliable.Therefore,wherethereisariskofexposure,surgeonsusedisposableinstruments.Tosterilizereusableinstruments,WHOcurrentlyrecommendscombineduseofastrongsolutionofsodiumhydroxideandextendedautoclavingat134?C."Autoclavingat134?Cfor5hrsortreatmentwith2NNaOHforseveralhoursisrecommendedforsterilizationofprions".sinceSodiumhydroxideoptionnotavailable,correctanswerisA
369.MostcommoncauseofHUSinchildren is a)Ecoli0157/H7 b)Styphi c)Shigella d)None CorrectAnswer-AAns.is'a'i.e.,EColi0157/H7ThemajorityofHUSinchildren(90%)isrelatedtoprototypicdiarrhoeaassociatedform,predominatelyinpreviouslyhealthychildren6monthsto4yearsofagewithapeakbetween1and2years.Shigatoxin-producingE.coli(STEC)isthemajorcauseofdiarrhoeaassociatedwithHUS.Specifically,Ecoliwithserotype0157:H7isthebacteriamostcommonlyassociatedwithHUS(90%)andisthemostvirulent.OthercommonbacteriaimplicatedinthecausationofHUSare:ShigelladysenteriaeSalmonellatyphiCampylobacterjejuniYersiniaspeciesPseudomonasspeciesClostridiumdifficile
370.Koch'spostulateisfullfilledbyall except a)M.tuburculosis b)E.coli c)T.pallidum d)None CorrectAnswer-CAns.is'c'i.e.,T.pallidumKochpostulatesRobertKochproposedaseriesofpostulatesthathavebeenappliedbroadlytolinkmanyspecificbacterialspecieswithparticulardisease.Koch'spostulatesare: 1. Themicroorganismshouldbefoundinallcasesofthediseasein questionanditsdistributioninthebodyshouldbeinaccordancewiththelesionsobserved. 2. Themicroorganismshouldbegrowninpurecultureinvitro(or outsidethebodyofthehost)forseveralgenerations. 3. Whensuchapurecultureisinoculatedintosusceptibleanimal species,thetypicaldiseasemustresult. 4. Themicroorganismmustagainbeisolatedfromthelesionsofsuch experimentallyproduceddisease.MicroorganismsthatdonotmeetthecriteriaofKoch'spostulates 1. Mycobacteriumleprae(leprosy)Cannotbeculturedinvitro2. Treponemapallidum(syphilis)Neisseriagonorrhoeae3. Noanimalmodelforexperimentalinfection MicroorganismthatpartiallysatisfythepostulatesE.coliinduceddiarrhea
371.Inclusionbodycontainingglycogenis seenin? a)Chlamydiatrachomatis b)Chlamydiapneumoniae c)Chlamydiapsittaci d)Alloftheabove CorrectAnswer-AAns.is'a'i.e.,ChlamydiatrachomatisCharacteristicsofthechlamydia Ctrachomatis Cpneumoniae Cpsittaci Inclusion Round, Large,variable Round,dense morphology vacuolar shape,dense Glycogenin Yes No No inclusions Elementarybody Pear-shaped, Round Round morphology round Susceptibleto Yes No No sulfonamides DNAhomology <10% 100%<10% toCpneumoniae Plasmid Yes No Yes Serovars 15 1 >4 Naturalhost Humans Humans Birds Modeof Personto Airborne Airbornebird transmission person,mother personto excretato toinfant person humans Majordiseases Trachoma,
Majordiseases Trachoma, Pneumonia, Psittacosis, STDs,infant bronchitis, pneumonia,fever pneumonia, pharyngitis, ofunexplained lymphogran- sinusitis origin uloma venereum
372.Cytolyticactivityofmembraneattack complexismodulatedby? a)FactorI b)FactorB c)FactorS d)FactorH CorrectAnswer-CAns.is'c'i.e.,FactorS
373.MostcommontypeofHPVassociated withcervicalcancer? a)6,11 b)5,8 c)16,18 d)6,8 CorrectAnswer-CAns.is`c'i.e.,16,18HPVDNAofoncogenictypes(Highrisk)inHPV-16,18,31,33and45associatedwithcervicalcancerHPV-6and11(LowriskHPV)associatedwithprecursorlesionsofcervicalcancer(CIN)andCondylomaAcuminatum.Inpatientswithepidermodysplasiaverruciformis,SquamouscellcancerdevelopfrequentlyatsitesinfectedwithspecificHPVtypes,including5and8.E6andE7genesofHPVareresponsibleforcarcinogenicity.
374.Frie'stestisusefulfordiagnosisof? a)Mycoplasma b)Rickettsia c)Sarcoidosis d)Chlamydia CorrectAnswer-DAns.is'd'i.e.,ChlamydiaFriestest(skinhypersensitivitytest)wasusedforLGV(causedbychlamydiatrachomatis).Butitisnotusednowbecauseofhighfalsepositiveresults.
375.Whichofthefollowingisanintermediate leveldisinfectant? a)2%glutarldyhyde b)Ethyleneoxide c)Hypochlorite d)None CorrectAnswer-CAns.is'c'i.e.,Hypochlorite
376.InfectiveformofT.brucei? a)Amastigote b)Trypomastigote c)Egg d)None CorrectAnswer-BAns.is'b'i.e.,Trypomastigote https://image.slidesharecdn.com/trypanosomaseminar1-170312074241/95/trypanosoma-1-4-638.jpg?cb=1489304612
377.Stainingmethodusedformycoplasma? a)Fontonamethod b)Lavidittimethod c)Dienesmethod d)None CorrectAnswer-CAns.is'c'i.e.,DienesmethodColoniesofmycoplasmamaybeseenwithahandlensbutarebeststudiedafterstainingbyDienesmethod.Forthis,ablockofagarcontainingthecolonyiscutandplacedonaslide.Itiscoveredwithacoversliponwhichanalcoholicsolutionofmethyleneblueandazurehasbeendried
378.Innateimmunityinvolves? a)T-cells b)B-cells c)Macrophages d)Antibodies CorrectAnswer-CAns.is'c'i.e.,MacrophagesMacrophagesandneutrophilsarephagocyticcellsthatengulfamicrobialpathogenafterithasbeenidentifiedbytheinnateimmunesystem
379.Goldenyellowjellyfungusis? a)Ttursurans b)Tmontegrophytes c)Trenellamesenterica d)Efloccosum CorrectAnswer-CAns.is'c'i.e.,TrenellamesentericaThetermjellyfungusissometimesappliedtoanyfunguswithajellylikefruitingbody,butitisespeciallyappropriateforthemembersofagroupoftexatraditionallyassignedtotheorderTremellales.LargestgenusisTremella,whichconsistsofabout80species.Tremellamesenterica(witchesbutter)isacommonlyencounteredspecieswhichhasorangetogoldenyellowfruitingbodies.Thereforeitisalsocalledasgoldenyellowjellyfungusoryellowbrainoryellowtrembler.
380.MacrophagetropicstrainsofHIVuse? a)CCR5 b)CXCR4 c)CCR4 d)None CorrectAnswer-AAns.is'a'i.e.,CCR5ReceptorsforHIVThereceptorforthevirusisCD4antigen,andthereforethevirusmayinfectanycellbearingtheCD4antigenonthesurfacethisisprimarilytheCD4+(Helper)TLymphocyteSpecificbindingofvirustoCD4receptorisbytheenvelopeglycoproteingp-I20.However,forinfectiontotakeplace,cellfusionisessential,whichisbroughtaboutbythetransmembranegp41.Entryofvirusintothecellsalsorequirescoreceptormolecule:- Tcell CXCR4 Macrophage CCR5
381.ABOisoantibodiesareofwhichclass a)IgG b)IgM c)IgD d)IgA CorrectAnswer-BAns.is'b'i.e.,IgMTheABOantigensrepresentcarbohydratemoetiespresentonerythrocytes.Invidualnaturallydevelopantibodies(calledisoantibodies),usuallyofIgMisotype,specificforABOantigensthatdonotexpress.IftheindividualreceivesatransfusionofbloodthatcontainsincompatibleABOantigens,isoantibodieswillcauseagglutinationofdonorcells.Thisprocessiscalledasisohemagglutination,theantigensarecalledisohemagglutinins.AslorememberAnti-RhantibodiesareofIgGclass
382.A4yearoldchildpresentswithacute waterydiarrheaandabdominalcramps.Stoolmicroscopyrevealstrophozoiteswithfallingleafmotility.Theetiologicalagentis? a)Entamoebahisiolutics b)Giardialamblia c)Trichomonastenax d)Balantidiumcoli CorrectAnswer-BAns.is'b'i.e.,GiardialambliaInacutegiardiasistrophozoitesshowthetypical"falling-leaf"motilityinwetmountexaminationoffaeces.Diagnosisofgiardiasis?Thegold-standardfordiagnosisofgiardiasisismicroscopicdemonstrationoftrophozoiteorcystorbothinfaeces.Inacutegiardiasistrophozoitesshowthetypical"falling-leaf"motilityinwetmountexaminationoffaeces.ThecharacteristicshapeandtwonucleiareseenafterstainingathinfaecalsmearwithField'sstain.Trophozoitesarealsopresentinduodenalfluid.Duodenalfluidcanbeeitheraspiratedorobtainedby"Stringtest"(Enterotest)forexamination.CystsofG.lambliaareoftenshedinthefaecesin"Showers",meaningthatmanycytesmaybepassedonadayandnoneontheother.Hence,todetectcyst-passersmultiple-samplearetobeexamined,preferablyfollowingconcentrationtechniqueslikezinc
sulphatefloatationorformaldetergentconcentrationtechnique.
383.Thehookwormthriveson? a)Wholeblood b)Plasma c)Serum d)RBC CorrectAnswer-BAns.is'b'i.e.,PlasmaHookwormsAncylostomaduodenaleOldworldhookwormNectoramericanusNewworldhookwormHabitatSmallintestine(Jejunum>duodenum>Ileum)InfectiveformFilariformlarvaModeofinfectionPenetrationofskinPlasmaformsthemainsourceofnourishmentforhookworm,theredbloodcellspassoutfromthewormpracticallyunchangedintothelumenofhost'sintestine.
384.InfectiveformofHookworms? a)Egg b)Rhabditiformlarva c)Filariformlarva d)None CorrectAnswer-CFilariformlarvaEggsarepassedinthestool,andunderfavorableconditions(moisture,warmth,shade),larvaehatchin1to2days.Thereleasedrhabditiformlarvaegrowinthefecesand/orthesoil,andafter5to10days(andtwomolts)theybecomefilariform(third-stage)larvaethatareinfective.
385.Allarenon-sporinganaerobesofmedical importanceexcept a)Actinomyces b)Bacteroides c)Clostridia d)Fusobacterium CorrectAnswer-CAns.is'c'i.e.,Clostridia
386.Thenumberofbacteriaonskinare a)10'-102 b)102-105 c)105-010 d)>1010 CorrectAnswer-DAns.is'd'i.e.,>1010Ithasbeencalculatedthatahumanadulthasabout1012bacteriaontheskin.
387.Thenumberofbacteriapercmofskin are? a)10'-102 b)102-103 c)105-1010 d)>10' CorrectAnswer-BAns.is`b'i.e.,102-103Densityofbacterialpopulationatmostsitesisbetween100-1000persquarecm.
388.WhichPassiveimmunityisalsoprovidedthroughcolostrumandbreast milk? a)IgG b)IgA c)IgE d)IgM CorrectAnswer-BAns.B.IgAPassiveimmunityisalsoprovidedthroughcolostrumandbreastmilk,whichcontainIgAantibodiesthataretransferredtothegutoftheinfant,providinglocalprotectionagainstdisease-causingbacteriaandvirusesuntilthenewborncansynthesizeitsownantibodies.ProtectionmediatedbyIgAisdependentonthelengthoftimethataninfantisbreastfed,whichisoneofthereasonstheWorldHealthOrganizationrecommendsbreastfeedingforatleastthefirsttwoyearsoflife.
389.Whichofthefollowingcelltypesarethe mostpotentactivatorofT-cell? a)Bell b)FollicularDendriticCells c)Maturedendriticcells d)Macrophages CorrectAnswer-CAns.(c)MatureDendriticcellsRef.Robins8/e,p192,Harrison18/e, p2657 "MaturedendriticcellsarethemostpotentactivatorofnaiveT-cell" DendriticCells:BonemarrowderivedcellsTherearetwotypesofcellswithdendriticmorphology:-Interdigitatingdendriticcells-FolliculardendriticcellsInterdigitatingdendriticcellsorjustdendriticcellsarethemostimportantantigenpresentingcellsforinitiatingprimaryimmuneresponseagainstproteinantigens.Thisisduetofollowingreasons:-Thesecellsarelocatedattherightplacetocaptureantigens,i.e.underepithelia,intheinterstitialofalltissue.-Theyexpressvarietyofreceptors(includingTLR,mannose)forcapturingmicrobes.-InresponsetomicrobesdendriticcellsexpressthesamechemokinereceptorsastonaiveT-cells.-TheyexpresshighlevelsofMHCclassIImoleculesaswellasco-stimulatorymoleculesB.7-1andB.7-2.OrinotherwordstheypossessallthemachineryneededforpresentingantigenstoandactivatingCD4+Tcells.
Ontheotherhandfolliculardendriticcells(doesnotarisefrombonemarrow)arepresentinthegerminalcentresoflymphoidfollicleswheretheytrapantigensboundtoantibodiesorcomplement.FolliculardendriticcellsplaysaroleinongoingimmuneresponsebypresentingantigenstoB-cellsandselectingtheB-cellsthathavethehighestaffinityfortheantigen.
390.Prozonephenomenonisdueto a)Antigenexcess b)Antibodyexcess c)False+vereaction d)False-vereaction CorrectAnswer-B:DAns.(b)and(d)AntibodyexcessandFalse-negativeRef.Ananthanarayan8/e,p104,9/105Zonephenomenon(seeninagglutinationandprecipitation)consistsof3parts: 1. Prozone=Abexcess=weakorabsentprecipitationreaction= False-ve 2. Zoneofequivalence=peakamountofprecipitation.3. Postzone=Agexcess=weakorabsentprecipitationreaction.
391.WhichofthefollowingStaphylococcal infectionisnottoxinmediated: a)Toxicshocksyndrome b)Scaldedskinsyndrome c)Foodpoisoning d)Septicshock CorrectAnswer-DAns.is(d)Septicshock ToxinmediatedillnessofS. Disease Toxininvolved -Toxicshocksyndrome Toxicshocksyndrometoxin -Foodpoisoning Enterotoxin -Staphylococcalscaldedskin Exfoliative/epidermolytic syndrome toxin Note:Septicshockisduetobacteremia.
392.Trueaboutinterferonis: a)Itisasyntheticantiviralagent b)Inhibitsviralreplicationincells c)Isspecificforparticularvirus d)None CorrectAnswer-BAns.(b)InhibitsviralreplicationincellsRt,11itliiilallarayl111CO,ppIiiiitC,i:;r,pInterferon(hostcodedprotein)hasnodirectactiononvirusesbutinhibitviralreplicationbyselectivelyinhibitingtranslationofviralm-RNAwithoutaffectingcellularm-RNA.IFNarenotvirusspecificbutspeciesspecific.Itisof3types:TypeCellsource.CelltargetBiologicalctivity IFNa(protein)orleukocyte Antiviralactivity;stimulates Allcells IFNAllcells TL.ell,macrophagesand NKcellactivity IFN13(glycoprotein) Allcells AllcellsDirectantitumoreffects orFibroblastIFN UpregulatesMHCclassIantigenexpression.Used therepeuticallyinviraland autoimmunedisease ?IFNy Regulatesmacrophage (glycoprotein)or Tcells Allcells andNKcellsactivation immuneIFN NK StimulatesIgsecretionbyB
NK StimulatesIgsecretionbyB cells cellsInductionofclassII histocompatibilityantigens TH1Tcelldifferentiation
393.ProteinAofstaphylococcusbindsto a)IgA b)IgG c)IgD d)IgE CorrectAnswer-BAns.is.b.IgG
394.Testtodifferentiatestaphylococcifrom micrococci: a)Catalasetest b)Coagulasetest c)Novobiosinsensitivity d)Oxidationfermentation CorrectAnswer-DOxidationfermentation
395.Mostcommonsiteforstaphylococcus carrier: a)Skin b)Nose c)Oropharynx d)Perineum CorrectAnswer-BAns.is.b.Nose
396.Crystalvioletbloodagarisusedfor whichbacteria? a)Corynebacteriumdiphtheriae b)Staphaureus c)-hemolyticstreptococcus d)Meningococcus CorrectAnswer-C-hemolyticstreptococcusCrystalvioletbloodagarisaselectivemediumforisolationofp-hemolyticgroup-Astreptococcus.oCrystalvioletpermitsthegrowthofstreptococcusbutinhibitsgrowthofothergrampositivebacteria(includingstaphylococcus)
397.Whichstreptodornaseismostantigenic inhumanbeings: a)A b)B c)C d)D CorrectAnswer-BAns.is.b.B
398.Achronicalcoholicispresentingwith clinicalfeaturesofmeningitis.MostlikelyorganismwhichwillgrowonCSFculture: a)Streptococcuspneumoniae b)N.meningitidis c)Listeriamonocytogenes d)F.coli CorrectAnswer-AStreptococcuspneumoniae
399.Heatingat60?Cfor30minutewould isolate: a)Staphylococci b)Enterococci c)Micrococci d)Streptococci CorrectAnswer-BEnterococci
400.Whichofthefollowingcanbeusedfor obtainingspecimenforisolationofmicroorganisminlaboratorydiagnosis: a)Meningococcalrash b)Bloodinstaphylococcalfoodpoisoning c)ThroatswabinRheumaticfever d)Bloodinpost-streptococcalGN CorrectAnswer-AAns.is.a'i.e.Meningococcalrash
401.Tcellsinlymphnodearepresentin: a)Paracorticalarea b)Mantlelayer c)Medullarycords d)Corticalfollicles CorrectAnswer-AAns.a.Paracorticalarea
402.Membraneattackcomplex(MAC)in complementsystemis: a)C3b b)C13 c)C5_9 d)C24 CorrectAnswer-CAns.c.C5_9
403.Complementcomponentsare: a)Lipids b)Proteins c)Lipoproteins d)Polysaccharide CorrectAnswer-BAns.b.Proteins
404.Whichisnottrueaboutmacrophages: a)ActivationbyIFN-y b)Majorcellsinchronicinflammation c)M2typeinvolvedininflammation d)Phagocyticcells CorrectAnswer-CAns.c.M2typeinvolvedininflammation
405.Nottrueaboutgasgangrene: a)MostcommoncauseisClperfringens b)Extensivenecrosisofmuscles c)Clperfringensproduceheat-labilespores d)Metronidazoleisthedrugofchoice CorrectAnswer-DAns.is.'d'i.e.Metronidazoleisthedrugofchoice
406.Naegler'sreactionisdueto: a)Coagulase b)Hyaluronidase c)Lecithinase d)Noneoftheabove CorrectAnswer-CAns.is.'c'i.e.Lecithinase
407.Trueaboutcorynebacteriumdiphtheriae: a)Alltypesproducetoxin b)Toxinproductionisdependentuponcriticalconcentrationof iron c)Heatstabletoxin d)InhibitcAMP CorrectAnswer-BAns.is.'b'i.e.Toxinproductionisdependentuponcriticalconcentrationofiron
408.Nottrueaboutcorynebacterium hormannii a)Adiphtheroid b)Non-pathogenicsaprophyte c)Toxigenic d)AlsoknownasCpseudodiphthericum CorrectAnswer-CAns.is.'c'i.e.Toxigenic
409.Ehrlichiachaffeensisiscausativeagents of a)HME b)HGE c)Glandularfever d)None CorrectAnswer-AAns.a.HME
410.Allaretrueaboutchromobacteritun violaceumexcept? a)Gramnegative b)Producesviolet-coloredpigment c)Normalflorainhuman d)Causescellulitis CorrectAnswer-CAns.c.Normalflorainhuman
411.Capsidofviralstructureis: a)Extracellularinfectiousparticle b)Proteincoataroundnucleicacid c)Enveloparoundavirus d)Noneoftheabove CorrectAnswer-BAns.b.Proteincoataroundnucleicacid
412.Trueaboutanthraxtoxinareallexcept: a)Hasthreefractions b)IncreasecAMP c)Codedbyplasmid d)Inhibitsproteinsynthesis CorrectAnswer-DAns.is.'d'i.e.Inhibitsproteinsynthesis
413.Regardingfungalcellwallallaretrue except: a)Containschitin b)Preventosmoticdamage c)Azolesactonthem d)Doesnotcontainpeptidoglycan CorrectAnswer-CAns.c.Azolesactonthem
414.CapsuleofBacillusanthracisisformed of: a)Polysaccharide b)Lipopolysaccharide c)Polypeptide d)Longchainfattyacids CorrectAnswer-CAns.is.'c'i.e.Polypeptide
415.Achildispresentingwithvomitingand abdominalpainafter5hoursofeatingsomefood.Themostlikelycausativeorgonism: a)Bacilluscereus b)Cl.perfringens c)Cl.botalinum d)V.cholerae CorrectAnswer-AAns.is.'a'i.e.Bacilluscereus
416.Allaretrueaboutlisteriaexcept: a)Grampositive b)PALCAMagarisusedforisolation c)Characteristictumblingmotilityat37?C d)Umbrellashapedgrowth CorrectAnswer-CAns.is.'c'i.e.,Characteristictumblingmotilityat37?CL.monocytogenesisagram-positive'coccobacillus'(coccoidrod)withatendencytooccurinchains.Peritrichousflagellaareproducedbythebacillusoptimallyat20-30?Cbutonlyscantilyornotatallat37?CCulturemediausedforisolationarebloodagar,chocolateagar,andPALCAMagar.Itgrowsonordinarymediawithinatemperaturerangeof1?to45?C.Mostcasesofhumandiseasearecausedbyserotypes1/2a,1/2band4b.Theorganismcanbefoundasapartofthegastrointestinalflorainhealthyindividuals.HumandiseaseduetoL.monocytogenesgenerallyoccursinthesettingofpregnancyorimmunosuppression.
417.Listeriaresistsphagocytosisin phagosomes(phagolysosomes)dueto: a)-hemolysin b)Caspases c)Cellmembraneadhesionmolecules d)Opacityassociatedprotein(OAP) CorrectAnswer-AAns.is.'a'i.e.,-hemolysinMostimportantstepinpathogenesisoflisteriosisisthesurvivalandmultiplicationofLmonocytogenesinphagocytes(macrophages),hostepithelialcellsandhepatocytes.*ThemostimportafltdeterrminantofpathogenesisklisteriolysinO(LLO),Abeta-hemolysin.LLOcauseslysisofmembraneofphagosomeswithinphagocytesandhelpsinintracellularsurvivalofLmonocytogenes.*Ironisanimportantvirulencefactor.Listeriaproducesiderophoresandareabletoobtainironfromtransferrin.Immunitytolisteriaisprimarycellmediated.Immunitycanbetransferredbysensitizedlymphocytesbutnotbyantibodies.
418.RenauldBraudphenomenonisseenis: a)Candidaalbicans b)Candidapscitasi c)Histoplasma d)Cryptococcus CorrectAnswer-AAns.a.Candidaalbicans
419.Reactivetuberculararthritis: a)Spinaventusa b)Pott'sdisease c)Poncet'sdisease d)None CorrectAnswer-CAns.is.'c'i.e.Poncet'sdisease
420.XDR-TBisdefinedasResistanceto: a)INHplusrifampicin b)FluoroquinolonesplusINHplusamikacin c)Fluoroquinolonesplusrifampicinpluskanamycin d)FluoroquinolonesplusINHplusrifampicinplusamikacin CorrectAnswer-DAns.is.'d'i.e.,FluoroquinolonesplusINHplusrifampicinplusamikacinExtensivedrugresistanceTB(XDR-TB)isreferredtoresistancetorifampicinandisoniazidaswellastoquinoloneandatleastoneofthefollowingsecondlinedrugkanamycin,capreomycinoramikacin.XDR-TB=resistancetoINH,rifampcin,Quinolone,andcapreomycin/kanamycin/amikacin
421.ModifiedZiehl-neelsenstainingisused for: a)Mycobacteriumtuberculosis b)Mycobacteriumbovis c)Nocardia d)Alloftheabove CorrectAnswer-DAns.is.'d'i.e.,Alloftheabove
422.Hansen'sbacillusisculturedin: a)LJmedium b)Robertson'scookedmeatmedium c)Footpadofmice d)Sabraud'sagar CorrectAnswer-CAns.is.'c'i.e.,Footpadofmice
423.PrimarycomplexofMbovisinvolves: a)Tonsilandlung b)Tonsilandintestine c)Tonsilandskin d)SkinandIntestine CorrectAnswer-BAns.is.'b'i.e.,TonsilandintestineAns.is.'b'i.e.,TonsilandintestinePrimarycomplexofMtuberculosis(infectionbyinhalation)i)Lunglesionii)EnlargedhilarlymphnodesoPrimarycomplexofMbovis(infectionbydrinkingmilk)i)Tonsilii)Cervicalnodesorintestine(ileocecalregionandmesentriclymphnodes)
424.Phagocytosisofmycobacterium tuberculosisbymacrophagesismainlymediatedby: a)IL6 b)IL3 c)IL12 d)IFNGamma CorrectAnswer-DAns.is.'d'i.e.,IFNGamma
425.Toxoplasmainchildrencauses: a)Chorioretinitis b)Conjunctivities c)Keratitis d)Papillitis CorrectAnswer-AAns.a.Chorioretinitis
426.Trueaboutwidaltest: a)Anti-0antibodypersistslonger b)0antigenofS.paratyphiisused c)H-antigenismostimmunogenic d)Felixtubeisusedfor'H'agglutinationlnar CorrectAnswer-CAns.is.'c'i.e.,H-antigenismostimmunogenic
427.NottrueaboutVipolysaccharidevaccine oftyphoid: a)Singledoseisgiven b)Revaccinationat3years c)Givenatbirth d)Givensubcutaneously CorrectAnswer-CAns.is.'c'i.e.,Givenatbirth
428.Salmonellaandshigellacanbe differentiatedfromotherenterobacteriaceaememberbyisolationon: a)MacConkeyagar b)Mannitolsaltagar c)BCYEmedium d)XLDagar CorrectAnswer-DAns.is.'d'i.e.XLDagarXLD(xyloseJysinedeoxycholate)agarisaselectivedifferentialmediumforisolationofGram-negativeentericpathogensfromfecalspecimensandotherclinicalmaterial.oItisespeciallysuitablefortheisolationofshigellaandsalmonellaspecias
429.ClinicalsignificanceofViantigenofS. typhiis: a)Helpsindiagnosis b)Highlyimmunogenic c)Mostimportantantigenforwidaltest d)AntibodyagainstVi-antigenisusedfordiagnosisofcarrier CorrectAnswer-DAns.is.'d'i.e.,AntibodyagainstVi-antigenisusedfordiagnosisofcarrier
430.ProteusisolatedfromapatientofUTIwill showwhichboichemicalreaction: a)Phenylpyruvicacidreaction b)Bileesculinreaction c)Colchicinesensitivity d)Bacitracinsensitivity CorrectAnswer-AAns.is.'a'i.e.,Phenylpyruvicacidreactionstofthemexceptprovidenciastrains,producepowerfulurease.-->Acharactersticfeatureofproteusbacilliis"PPAreaction'-->Itisduetopresenceofenzymepheny'alaninedeaminasewhichconvertsphenylalaninetophenylpymvicacid
431.Hebranoseiscausedby: a)Frischbacillus b)Staphaureus c)Pseudomonas d)C.diphtheriae CorrectAnswer-AAns.is.'a'i.e.,Frischbacillus
432.Amoebiasisisnottransmittedby: a)Feco-oralroute b)Sexualtransmission c)Bloodandbloodproducts d)Vectortransmission CorrectAnswer-DAns.d.Vectortransmission
433.Trypanosomacruziistransmittedby: a)Tsetsefly b)Reduviidbug c)Culexmosquito d)Sandfly CorrectAnswer-AAns.a.Tsetsefly
434.AbsenceofVi-antibodyinatyphoid patienthas: a)Goodprognosis b)Badprognosis c)Norelationwithprognosis d)Indicateswidalnegative CorrectAnswer-BAns.is.'b'i.e.,Badprognosis
435.Duodenalaspirateisusedindiagnosis of: a)Ehistolytica b)Giardialamblia c)Taeniasolium d)Leishmania CorrectAnswer-BAns.b.GiardialambliaDuodenalaspirateisusedforGlambia,osinesis,Fheptica,andSstercoralis.
436.Recrudescencesarecommonlyseenin whichmalaria: a)Pvivax b)Povale c)Pmalariae d)Pfalciparum CorrectAnswer-DAns.d.Pfalciparum
437.CharcotLeydencrystalinstoolinseen in: a)Amoedbicdysentery b)bacillarydysentery c)Shigella d)bacilluscereus CorrectAnswer-AAns.a.Amoebicdysentery
438.Bacteriathatcangroweveninthe presenceofantiseptic: a)Staphylococcus b)Streptococcus c)E.coli d)Pseudomonas CorrectAnswer-DAns.is.'d'i.e.,Pseudomonas
439.Whichofthefollowingisnon-motile: a)Pseudomonasaeruginosa b)Burkholderiamallei c)Burkholderiapseudomallei d)Noneoftheabove CorrectAnswer-BAns.is.'b'i.e.,Burkholderiamallei
440.Pneumonicplagueisspreadby: a)Biteofinfectedflae b)Directcontactwithinfectedtissue c)Ingestionofcontaminatedfood d)Dropletinfection CorrectAnswer-DAns.is.'d'i.e.,Dropletinfection
441.Izumifeveriscausedby: a)Pseudomonasaeruginosa b)Burkholderiamallei c)Yersiniapseudotuberculosis d)Pasteurellamultocida CorrectAnswer-CAns.is.'c'i.e.,Yersiniapseudotuberculosis
442.Schistosomiasisisanexmpleof: a)Meta-zoonoses b)Cyclo-zoonoses c)Direct-zoonoses d)Sporo-zoonoses CorrectAnswer-AAns.a.Meta-zoonoses
443.Trueaboutdiphyllobothrium: a)Manissinglehost b)Irondeficiencyanemiaisseen c)Operculatedeggisdiagnostic d)Fishisthedefinitivehost CorrectAnswer-CAns.c.Operculatedeggisdiagnostic
444.Unsegmentedeggsareinwhich parasite? a)Trichuristrichura b)Ancylostoma c)Necatoramericanus d)Dracunculus CorrectAnswer-AAns.a.Trichuristrichura
445.Flamecellsareseenin: a)Protozoa b)Cestode c)Nematodes d)None CorrectAnswer-BAns.b.CestodeFlamecell(alsocalledsolenocyte)istheexcretorycellincestodesandtrematodes,thenumberandarrangementofwhichisusedasabasisforidentification.Thecellhasatuftofcilia,whosebeatingresemblestheflickeringofaflame.Theflamecellsopenintoacollectingtubule.
446.Cholangiocarcinomaiscausedby: a)Giardialamblia b)Clonorchisinfestation c)Paragonimusinfestation d)Ascarisinfestation CorrectAnswer-BAns.b.Clonorchisinfestation
447.Brazilianpurpuricfeveriscausedby: a)Bordetellapertussis b)Haemophilusaegypticus c)Haemophilusduceryi d)Haemophilusparinfluenzae CorrectAnswer-BAns.is.'b'i.e.,Haemophilusaegypticus
448.Granulomainguinaleiscausedby: a)H.ducreyi b)Chlamydiatrachomatis c)Treponemapallidum d)Calymmatobacterium CorrectAnswer-DAns.is.'d'i.e.,CalymmatobacteriumGranulomalenerutn(granulomainguinal)-->Calymmatobacterium
449.Pseudobuboseenin: a)Chancroid b)Syphilis c)Lymphogranulomainguinale d)Lymphogranulomavenerum CorrectAnswer-CAns.is.'c'i.e.,Lymphogranulomainguinale
450.Pontiacfeveriscausedby: a)Legionella b)Listeria c)Scrubtyphus d)Leptospira e)Rickettsia CorrectAnswer-AAns.(a)LegionellaPontiacfeverisamildnonfatalinfluenzalikeillnesscausedbyLegionellapneumophila.Pontiacfexc,AnacuteselflimitingfluelikeillnesswithIPof24-48hoursMalaise,fatigueandmyalgiaarethemostfrequentpresentingsymptomsPneumoniadoesn'tdevelop.Completerecoverytakesplace,withoutantibiotictherapy.Diagnosisisestablishedbyantibodydetection.
451.Trueaboutlegionella: a)Mostcommonmodeoftransmissionisaerosolinhalation b)Thereisnomantomantransmission c)Prolongedcarrierarecommon d)Allaretrue CorrectAnswer-BAns.is.'b'i.e.,Thereisnomantomantransmission
452.Congenitalvaricellainfectioncausesall except: a)Macrocephaly b)Limbhypoplasia c)Corticalatrophy d)Cicatrix CorrectAnswer-AAns.a.Macrocephaly
453.Whichpoxwontgrowinegg,animal cells: a)Cowpox b)Vaccinia c)Variola d)Molluscum CorrectAnswer-DAns.d.Molluscum
454.Diagnosisofrotavirusisby: a)Stoolantigen b)Stoolantibody c)Stoolculture d)Bloodantibody CorrectAnswer-AAns.is'a'i.e.,Stoolantigen[Ref:Hanison18n/ep.1591,1592;Greenwood1&/ep.5251InRotavirusdiarrhoea,largeno.ofvirusesareshedinfaeces(atthepeakofthedisease,asmanyasl0rrvirusparticlescanbedetectedpermloffeces).Thesevirusescanbeeasilydetectedbythefollowingmethods:i)Enzymeimmunoassay(ELISA)Itoffersapproximately90%specificity&sensitivityfordetectionofvirusinstools.ii)Latexagglutinationiii)Immuneelectronmicroscopy-->Viralsheddingdetectablebythesemethodsusuallysubsideswithinaweek-->VirusinstoolscanbedetectedforlongerperiodsbyusingtechniquesfordetectingviralRNAs,suchasPCR,Gelelectrophoresis,probehybridization.
455.Whichofthefollowingbelongsto Herpesviridae: a)Variola b)Adenovirus c)HPV d)RKvirus CorrectAnswer-DAns.d.RKvirus
456.Whichisnotapoxvirus: a)Vacciniavirus b)Molluscumcontagiosum c)Tanapoxvirus d)Coxsackievirus CorrectAnswer-DAns.d.Coxsackievirus
457.Trueaboutchlamydiaareallexcept: a)Obligateintracellularorganism b)Grampositive c)Reticulatebodyismetabolicallyactive d)Replicatebybinaryfission CorrectAnswer-BAns.is.'b'i.e.,Grampositive
458.Indianticktyphusiscausedby: a)Rtyphi b)Rconorii c)Rakari d)Cburnetii CorrectAnswer-BAns.is.'b'i.e.,Rconorii
459.Chlamydiapneumoniaecausescauses: a)LGV b)Atherosclerosis c)Inclusionconjunctivitis d)Trachoma CorrectAnswer-BAns.is.'b'i.e.,Atherosclerosis
460.Bartonellaquintanacauses: a)Trenchfever b)Scrubtyphus c)Endemictyphus d)Epidemictyphus CorrectAnswer-AAns.is.'a'i.e.,Trenchfever
461.Whatistrenchfever: a)Q-fever b)5-daysfever c)Boutonneusefever d)Indianticktyphus CorrectAnswer-BAns.is.'b'i.e.,5-daysfever
462.Brill-Zinsserdiseaseis: a)RecrudescentofRprowazekiiinfection b)RecrudescentofRtyphiinfection c)RecrudescentofRconoriiinfection d)None CorrectAnswer-BAns.is.'b'i.e.,RecrudescentofRtyphiinfection
463.EscharisseeninalltheRickettsial diseasesexcent: a)Scrubtyphus b)Rickettsialpox c)Indianticktyphus d)Endemictyphus CorrectAnswer-DAns.is.'d'i.e.,Endemictyphus
464.BubusformiswhichstageofLGV: a)Prmary b)Secondary c)Tertiary d)Latent CorrectAnswer-BAns.is.'b'i.e.,Secondary
465.Leptospirosisistransmittedby: a)Rat b)Cat c)Dog d)Fish CorrectAnswer-AAns.is.'a'i.e.,Rat
466.Vincent'sanginaiscausedbyBorrelia vincentiialongwith: a)Lactobacillus b)Lactobacillus c)Fusobacterium d)Bacteroides CorrectAnswer-CAns.(c)Fusobacterium
467.Mostcommonformofleptospirosis: a)Weil'sdisease b)Ictericform c)Hepatorenalform d)Anictericform CorrectAnswer-DAns.(d)AnictericformItismostcommon(90%)andmildform.Mostcommonfindingkfnerwithconjunctivalsuftrcion
468.ColoradoTicfeveriscausedby: a)Filoviridae b)Reoviridae c)Coronaviridae d)Calciviridae CorrectAnswer-BAns.b.Reoviridae
469.Mediumusedforantibioticsensitivity: a)CLEDagar b)Hektoenagar c)Mueller-Hintonagar d)Saltmilkagar CorrectAnswer-CAns.is.'c'i.e.,Mueller-HintonagarAntibioticsensitivitytestingAntibioticsensitivitytestingiscarriedouttodetermineappropriateantibiotictobeusedforaparticularstrainisolatedfromclinicalspecimens.Antibiotictestingcanbecarriedoutbytwobroadmethods:a)Discdiffusiontestsb)DilutiontestsA)DiscdiffusiontestsTherearemostcommonlyusedmethodstodetermineantibioticsusceptibility.Discsimpregnatedwithknownconcentrationofantibioticsandareplacedontheculturemediumthathasbeeninoculatedwithacultureofbacteriumtobetested.Antibioticsensitivityisdeterminedbyzoneofinhibitionofbacterialgrowtharoundthedisc.SelectionofmediaMediumthatsupportsbothtestandcontrolstrainsisselectedforcarryingoutantibioticsusceptibilitytesting.Forexample:Muller-Hintonagarisusedforgram-negativebacilliandstaphylococcusspp.
Bloodagarisusedforstreptococcussppandenterococcusspp.ChocolateagarisusedforHaemophilusinfluenzaeWellcotestmediumusesantibioticssulfonamideandcotrimoxazoleMueller-HintonagarismostcommonlyusedmediumforantibioticsensitivitytestingTypeofdiscdiffusiontest.Discdiffusiontestsarefollowingtypes:?i)Kirby-Bauerdiscdiffusionmethod-mostcommonlyused.ii)Stokediscdiffusionmethodiii)Primarydiscdiffusiontest
470.Sterilizationofculturemediacontaining serumisby: a)Autoclaving b)Microporefilter c)Gammaradiation d)Gammaradiation CorrectAnswer-AAns.(a)Autoclaving
471.Incubationperiodofmeaslesis: a)18-72hours b)10-14days c)3-4days d)20-25days CorrectAnswer-BAns.b.10-14days
472.ViralDNAisintegratedintoBacterial DNAin: a)Transduction b)Lysogenicconversion c)Transformation d)Conjugation CorrectAnswer-BAns.(b)Lysogenicconversion
473.Whichinfluenzaestrain,notofhuman originandcancausepandemic: a)HiNi b)H2N2 c)H5Ni d)H9Ni CorrectAnswer-CAns.c.H5N1
474.Trueaboutinfluenzavaccine: a)Livevaccineisusedmostcommonly b)Livevaccineisgivenbynasaldrops c)Killedvaccineisgivenintramuscularindeltoid d)Allarecorrect CorrectAnswer-BAns-BLiveattenuatedvaccines-->TheseareusedasnasaldropsKilledvaccine-->Itisusedmosfcommonly.Itisgivensubcutaneouslyin2doses,3-4weeksapart.Protectiveefficacyis70-90%anddurationofprotectionis3-6months.
475.Trueaboutrotavirusvaccine: a)Killedvaccine b)Givensubcutaneous c)Pentavalentvaccine d)Shouldbegivenbefore5years CorrectAnswer-CAns.c.Pentavalentvaccine
476.Bindingofgp120causes: a)Infectionoftargetcell b)Facilitationofco-receptor c)Fusingofvirusandtargetcell d)None CorrectAnswer-BAns.b.Facilitationofco-receptor
477.HIVenvelopisformedby: a)Hostcell b)Virus c)Both d)None CorrectAnswer-CAns.c.Both
478.WhichHIV-virusismoredangerous: a)HIV-1 b)HIV-2 c)Botharesame d)Itdependsonhostfactors CorrectAnswer-AAns.a.HIV-1
479.Mostcommonmodeoftransmissionof HIVsexualtransmission: a)Blood&bloodproducts b)Occupational c)Perinatal d)Breastfeeding CorrectAnswer-AAns.a.Blood&bloodproducts
480.Flaskshapedulcersinintestinecaused by a)Giardialamblia b)Entamoebahistolytica c)Helicobacterpylori(H.pylori) d)E.vermicularis CorrectAnswer-BAnswerB.EntamoebahistolyticaDiseaseoccurswhenamoebacomesincontactwiththecellsliningtheintestine.Itthensecretesthesamesubstancesitusestodigestbacteria,whichincludeenzymesthatdestroycellmembranesandproteins.Thisprocesscanleadtopenetrationanddigestionofhumantissues,resultingfirstinflask-shapedulcerationsintheintestine.Entamoebahistolyticaingeststhedestroyedcellsbyphagocytosisandisoftenseenwithredbloodcells(aprocessknownaserythrophagocytosis)insidewhenviewedinstoolsamples
481.Whattypeofculturemediaisusedfor Ligionella? a)(BCYE)agarmedia b)MacConkeyagar c)Baird?Parkeragar d)Sabouraud'sagar CorrectAnswer-AAnswer:A.(BCYE)agarmediaBCYEisselectiveforcertainGram-negativebacteria,especiallyLegionellapneumophila.Theorganismsarenutritionallyfastidious,non-sporeforming,aerobic,gram-negative,slenderrods.Mediacontainingcysteine,yeastextract,a-ketoglutarate,andiron(BCYE)arerequiredforisolationofLegionella.SelectiveBCYE(mediumcontainingantibiotics),isrecommendedforspecimenslikelytobecontaminatedwithotherbacteria.
482.SpecialStainforcryptococcus: a)ZNstain b)Gramstain c)Mucicarminestain d)Malachitegreen CorrectAnswer-CAns:C.MucicarminestainMucicarminestainprovidesspecificstainingofpolysaccharidecellwallinC.neoformans.Thisislimitedtomicroorganismswithacellwallthatiscomposed,atleastinpart,ofapolysaccharidecomponent.
483.A36yrsoldmalepatientc/,ocoughcold fever/rustysputum/sputumnegfortb,h/ooftravelinchina&eatencrab,Nametheinfection a)Paragonimuswestermani b)Faciolahepatica c)Fasciolopsisbuski d)Entamoebahistolytica CorrectAnswer-AAns:A.Paragonimuswestermani(lungfluke).Duringinvasionandmigrationoftheflukes,diarrhea,abdominalpain,fever,cough,urticaria,hepatosplenomegaly,pulmonaryabnormalities,andeosinophiliamaydevelop.Unembryonatedeggsarepassedinthesputumofahuman.Duringthechronicphase,thelungsaredamagedmost,butotherorgansmaybeinvolved.TheclinicalpictureresemblesandisoftenconfusedwithTB.Praziquantelisthetreatmentofchoice.
484.Microbiologicaltestfordiagnosing leptospirainfection? a)Coldagglutination b)Standardagglutination c)Microscopicagglutinationtest(MAT) d)Noneofthese CorrectAnswer-CAnswer:C.Microscopicagglutinationtest(MAT)Dark-fieldmicroscopyorbyimmunofluorescenceorlightmicroscopyafterappropriatestainingusedMicroscoplcagglutinationtest[MAT](GoldStandard)alsoMacroscopicagglutlnationtestDifferentialdiagnosislistforleptospirosisisverylargeduetodiversesymptoms.
485.Discdiffusionmethodisalsoknownas a)KirbyBauer b)VDRL c)Darkfieldmicroscopy d)Noneofthese CorrectAnswer-AAnswer:A.KirbyBauerThediskdiffusiontest,oragardiffusiontest,orKirby?Bauertest(disc-diffusionantibioticsusceptibilitytest,disc-diffusionantibioticsensitivitytest,KBtest),isatestoftheantibioticsensitivityofbacteria.Itusesantibioticdiscstotesttheextenttowhichbacteriaareaffectedbythoseantibiotics.Inthistest,waferscontainingantibioticsareplacedonanagarplatewherebacteriahavebeenplaced,andtheplateislefttoincubate.Ifanantibioticstopsthebacteriafromgrowingorkillsthebacteria,therewillbeanareaaroundthewaferwherethebacteriahavenotgrownenoughtobevisible.Thisiscalledazoneofinhibition
486.Rubellavirusbelongstowhichfamily? a)Rheovirus b)Togavirus c)Picornavirus d)Orthomyxo CorrectAnswer-BAnd.B.TogavirusRubellavirus(RuV)isthepathogenicagentofthediseaserubella,andisthecauseofcongenitalrubellasyndromewheninfectionoccursduringthefirstweeksofpregnancy.RubellavirusistheonlymemberofthegenusRubivirusandbelongstothefamilyofTogaviridae,whosememberscommonlyhaveagenomeofsingle-strandedRNAofpositivepolaritywhichisenclosedbyanicosahedralcapsid.
487.Whichofthefollowinginfection resembleserythroblastosis? a)EBV b)CMV c)HSV d)STAPHYLOCOCCUS CorrectAnswer-BANSWER:B.CMVCytomegalovirusinfectionisacommonherpesvirusinfectionwithawiderangeofsymptoms:fromnosymptomstofeverandfatigue(resemblinginfectiousmononucleosis)InfectionwithCMV,likethatwithEpstein-Barrvirus(EBV,atype4herpesvirus),cancauseatypeofinfectiousmononucleosisinadolescentsandyoungadults.BothCMVandEBVmononucleosiscausefeverandfatigue.ButEBValsocausesaseveresorethroat.CMVdoesnot.
488.Diagnostictestforneurosyphilis a)VDRL b)RPR c)TPI d)FTA-ABS CorrectAnswer-AAnswer:A.VDRLExaminationofCSFforpleocytosis,increaseproteinconcentration,VDRLreactivity.ApositiveCSFVDRLmakesthediagnosisofneurosyphilis.Ifbothtesti.e.VDRLandFTA-ABSIgM(specific)testarepositiveintheinfantthencongenitalsyphilisshouldbestronglysuspectedandthechildshouldbetreated.Apositivetestconfirmsneurosyphilisbutanegativeresultdoesnotruleoutneurosyphilis.DuetothelowsensitivityoftheCSFVDRL,fluorescenttreponemalantibodyabsorptiontest(FTA-ABS)canbeusedtosupplementVDRL.
489.Apatientishavinggastrointestinal problemsincludingabdominalpainanddistension,bloodyormucus-filleddiarrhea,andtenesmus,withrectalprolapse,Astool,ovaandparasitesexamrevealsthepresenceoftypicalBarrel-shapedeggs,possiblecausativeagentis? a)Campylobacter b)Clostridiumdifficile c)Giardialamblia d)Trichuris CorrectAnswer-DAnswer:D.Trichuriswhipwormcancausegastrointestinalproblems,suchasabdominalpain,diarrhea,mucousorbloodystoolsweightloss,painfulurination,andweakness.Rectalprolapseisahallmark,albeitrare,symptomofaheavyT.trichiurainfectionthatoccursinchildrenmorefrequentlythanadults.Whenrectalprolapseoccurs,wormscanoftenbeidentifiedontheedematousrectum.Inawhipworminfection,therectumlosesitsinternalsupportbecausethewormsburytheirthinheadsintotheintestinallining,looseningtheelasticepitheliumandweakeningthesurroundingmuscles.
490.Contactisolationisdonefor a)MRSA b)Mumps c)Diphtheria d)Asthama CorrectAnswer-CAnswer:C.DiphtheriaAtypeofbacteriacalledCorynebacteriumdiphtheriaecausesdiphtheria.Theconditionistypicallyspreadthroughperson-to-personcontactorthroughcontactwithobjectsthathavethebacteriaonthem,suchasacuporusedtissue.Evenifaninfectedpersondoesn'tshowanysignsorsymptomsofdiphtheria,they'restillabletotransmitthebacterialinfectionforuptosixweeksaftertheinitialinfectionThebacteriamostcommonlyinfectyournoseandthroat.Onceyou'reinfected,thebacteriareleasedangeroussubstancescalledtoxins.Thetoxinsspreadthroughyourbloodstreamandoftencauseathick,graycoatinginnose,throat,lungs.
491.Achildissufferingfromrecurrent chronicinfectionswithencapsulatedbacteriaisduetodeficiencyofsubclass. a)IgG1 b)IgG2 c)IgG3 d)IgG4 CorrectAnswer-BAnswer:B.IgG2IgG2antibodiesarepredominantlyagainstthepolysaccharide(complexsugar)coating(capsule)ofcertaindisease-producingbacteria(suchas,StreptococcuspneumoniaeandHaemophilusinfluenzae).Inyoungchildren,theabilitytomakeIgG2antibodiestothepolysaccharidecoatingsofbacteriadevelopsmoreslowlythantheabilitytomakeantibodiestoproteins.
492.D.O.Cforisospora a)PenicillinG b)Benzathinepenicillin c)Co-trimoxazole d)Albendazole CorrectAnswer-CAnswer:C.Co-trimoxazoleThemostcommonantibioticthatisprescribedisco-trimoxazole(trimethoprimsulfamethoxazole),morecommonlyknownasBactrim,Septra,orCotrim.ForImmunocompetenthostsPreferedregimen:Trimethoprim-sulfamethoxazole160mg/800mgPObidfor7-10days..
493.CoxsackievirusA16causes a)Yellowfever b)Hand-foot-mouthdisease c)Rockymountainspottedfever d)Encephalomyocarditis CorrectAnswer-BAnswer:B.Hand-foot-mouthdiseaseHand,FootandMouthDisease(HFMD)iscausedbycoxsackieA-16ThevirusesthatcauseHFMDarespreadthroughclosepersonalcontact,throughtheairfromcoughingandthefecesofaninfectedperson.CoxsackievirusA16isthemostcommoncause,andenterovirus71isthesecond-mostcommoncause.Otherstrainsofcoxsackievirusandenteroviruscanalsoberesponsible.Ittypicallybeginswithafeverandfeelinggenerallyunwell.Thisisfollowedadayortwolaterbyflatdiscoloredspotsorbumpsthatmayblister,onthehands,feetandmouthandoccasionallybuttocksandgroin.
494.Pneumocystisjeroviciis: a)AssociatedwithCMV b)Diagnosisisbysputummicroscopy c)Seenonlyinimmunocompromisedpatients d)Alwaysassociatedwithpneumatocele CorrectAnswer-BAnswer:B.DiagnosisisbysputummicroscopyHumanisolateof.PneumocystiswhichisassociatedwithseverepneumoniainimmunocompromisedstateparticularlyAIDS.P.jeroviciisanextracellularpathogen.Growthinthelungislimitedtosurfactantlayerabovealveolarepithelium.Serologicevidencesuggestthatmostindividualsareinfectedinearlychildhood(thusoption"c"iswrong)butthepneumoniaisseenonlyinimmunocompromisedstate.DiagnosisismadebydetectionoforganisminproperspecimenSputum:Quickandnoninvasive.Broncho-alaeolarlaoage(BAL)fluid:Mainstayofpneumocystisdiagnosis.Transbronchialbiopsy:IfdiagnosiscannotbemadebyBAL.
495.Allaretrueaboutcongenital ToxoplasmosisEXCEPT a)Chorioretinitis b)Conjunctivitis c)Hydrocephalus d)Cerebralcalcification CorrectAnswer-BAnswerB.ConjunctivitisOccursonlywhenmothergetsprimarytoxoplasmosisinfectionwhetherclinicalorasymptomaticduringpregnancyor<6monthsbeforeconception(i.e.noriskifacquired>6monthsbeforeconception).Asgestationalageisincreased,riskoftransmissiontofetusincreased,i.e.max.in3rdtrimesterwhileseverityoffetaldamageisdecreased,i.e.infantisusuallyasymptomaticifinfectiontransmitin3rdtrimester.Chorioretinitisisusuallytreatedwithacombinationofcorticosteroidsandantibiotics.Itcauses:hydrocephalous,diffusecerebralcalcification,hepatosplenomegaly,mentalretardationmyocarditis,lymphadenitis,microencephaly,myocarditis,chorioretinitis,multiorganfailure,Pneumonitis
496.trueaboutTRIADcongenitalrubella syndrome a)PDA,cataractanddeafnessisseen b)Hepatosplenomegaly,mentalretardation,deafness c)Chorioretinitis,multiorganfailure,pneumonitis d)Noneofthese CorrectAnswer-AAnswer:A.PDA,cataractanddeafnessisseenCongenitalrubellasyndrome(CRS)canoccurinadevelopingfetusofapregnantwomanwhohascontractedrubella,usuallyinthefirsttrimester.Ifinfectionoccurs0?28daysbeforeconception,theinfanthasa43%riskofbeingaffected.Infectionin2ndtrimester?maybedeafnessonly.>6wks?nomajorabnormalitiesDiagnosis:Isolationofvirusincellculturesofthroatsamples,urineorothersecretions.DetectionofIgMinsingleserumsampleshortlyafterbirth.PersistanceofRubellaIgGantibodiesserumbeyond1yearorrisingantibodytiteranytimeduringinfancyinanunvaccinatedchild
497.Weilfelixreactioninscrubtyphusis/are positivefor: a)OX-19 b)OX-2 c)BothOX-19&OX-2 d)OX-K e)OX-19,OX-2&OX-K CorrectAnswer-DAns:d.OX-K[RefAnanthanarayan9th/410;MedicalMicrobiologybyGreenwood16th/373]Thisreactionisanagglutinationtestinwhichseraaretestedforagglutininstothe0antigensofcertainnon-motileProteusstrainsOX-19,OX-2&OX-XThebasisoftestisthesharingofanalkali-stablecarbohydrateantigenbysomerickettsiae&bycertainstrainsofproteus,P.vulgarisOX19&OX2&P.mirabilisOXK. disease OX-19 OX-2 OX-K Epidemic +++ + _ typhusBrill- Usually(? Zinsser ve)orweakly - disease (+ve) Endemic +++ +/- - typhusTickbornespotted ++ ++ - fever
feverScrub - - +++ typhus
498.Thecorrectorderofgramstainingis a)GentianvioletIodineCarbolfuchsin b)IodineGentianvioletCarbolfuchsin c)CarbolfuchsinIodineGentianviolet d)CarbolfuchsinGentianvioletIodine CorrectAnswer-AAnswer-A-GentianvioletIodineCarbolfuchsin 1. Applicationoftheprimarystain(crystalviolet).Gentianvioletalso knownascrystalvioletstainsallcellsblue/purple 2. Applicationofmordant:Theiodinesolution(mordant)isaddedto formacrystalviolet-iodine(CV-I)complex;allcellscontinuetoappearblue. 3. Decolourizationstep:Thedecolourizationstepdistinguishesgram- positivefromgram-negativecells.Theorganicsolventsuchasacetoneorethanolextractsthebluedyecomplexfromthelipid-rich,thin-walledgram-negativebacteriatoagreaterdegreethanfromthelipid-poor,thick-walled,gram-positivebacteria.Thegram-negativebacteriaappearcolourlessandgram-positivebacteriaremainblue. 4. Applicationofcounterstain(safranin):Thereddyesafraninstains thedecolourizedgram-negativecellsred/pink;thegram-positivebacteriaremainblue.NOTEIfyouarestrugglingtorememberthestainingreagentsusedinthisprocedureandtheirorderyoucanrememberthissentence"ComeInAndStain"i.e.theorderisCrystalviolet,Iodine,Alcohol/AcetoneandthefinaloneisSafranin.
499.Non-parasiticeosinophiliaiscausedby infectionwith- a)Staphylococcus b)Ehrlischia c)Coccidioidomycosis d)Candidiasis CorrectAnswer-CAns.is'c'i.e.,Coccidioidomycosis[RefDiagnostichematologyp.332]"Oneoftheveryfewnon-parasiticinfectionsthatregularlycauseeosinophiliaisCoccidioidomycosis,afungalinfection.atypicalpneumonia
500.Candidiasofpenisis? a)Thrush b)Leukoplakia c)Balanitis d)None CorrectAnswer-CAns.is'c'i.e.,Balanitis[RefEssentialsofmedicalmicrobiologyp.712]Candidalinfectionsareidentifiedbytheirlocationonthebodyasfollows:Axillae,underpendulousbreasts,groin,interglutealfolds:intertrigo.Glanspenis:balanitisFollicularpustules:candidalfolliculitisNailfolds:candidalparonychiaMouthandtongue:oralcnadidiasis(thrush)Areaincludedunderdiaper-diaperdermatitis
501.Allculturemediaareusedforantibiotic susceptibilityexcept- a)Tetrathionate-F b)Bloodagar c)Chocolateagar d)Muller-Hintonagar CorrectAnswer-AAns.is'a'i.e.,Tetrathionate-F*TheKirby-Bauerdiskdiffusionmethodisoneofthemostwidelypracticedantimicrobialsusceptibilitytests(AST).*Itisaffectedbymanyfactorsamongwhicharethemediaused.*Mueller-Hintonagar(MHA)isthestandardmediumrecommendedinguidelines.*Mueller-Hintonhasafewpropertiesthatmakeitexcellentforantibioticuse....-Starchisknowntoabsorbtoxinsreleasedfrombacteria,sothattheycannotinterferewiththeantibiotics.-Second,itisalooseagar.Thisallowsforbetterdiffusionoftheantibioticsthanmostotherplates.
502.Cellulitissurroundingdiabeticulceris mostlycausedby? a)Streptococcuspyogenes b)Staphylococcus c)Mixedorganisms d)Pseudomonas CorrectAnswer-CAns.is'c'i.e.,Mixedorganisms[RefEssentialsofmedicalmicrobilogyp.712]"Amixtureofgram-positivecocciandgram-negativeacrobesandanaerobesisoftenimplicatedincellulitissurroundingdiabeticanddecubitusulcers".
503.
Apaitentoperatedfortransurethralresectionofprostate[TURP]developsUTI.Theorganismmostcommonlygrownonculturewillbe- a)Proteus b)E.coli c)Pseudomonas d)Listeria CorrectAnswer-BAns.is'b'i.e.,E.coli[Refwww.jcam.com]MostcommonorganismcausingUTIaftertransurethralprostectomyisEcoli.
504.Loeffer'sserumisanexampleof a)Basalmedium b)Simplemedium c)Complexmedium d)Enrichmentmedium CorrectAnswer-CAns.is'c'i.e.,Complexmedium[RefAnanthanarayan8th/e.p.140]Loeffler'smediumisanenrichedmediumAtypeofspecial(complex)medium.
505.Mostcommonorganismgrowninurine cultureofpregnantwomanwithasymptomaticbacteriuria? a)Proteus b)E.coli c)Staphaureus d)Pseudomonas CorrectAnswer-BAns.is'b'i.e.,E.coliAsymptomaticbacteriuriaisthepresenceofbacteriainavoidedurinesampleandiscausedbybacterialcolonizationoftheurinarytract.Itaffectsabout5to10percentofbothsexuallyactiveandpregnantwomen.Asymptomaticbacteriuriaislessprevalentinmen.Asthenameindicates,asymptomaticbacteriuriadoesnotcausesymptoms.Theconditionsimplyreferstothedetectionofbacteriainaurinesample.Nonetheless,thereisgoodreasontobeconcernedaboutthisinfection,particularlyifyouarepregnant,becauseitcanleadtoasymptomaticupperurinarytractinfection(namely,pyelonephritis),whichcancomplicatepregnancy.Bacteriaaretypicallyintroducedintotheurinarytractduringintercourseorwhenwipingafterabowelmovement.ThebacteriumE.coliisresponsibleforatleast75to80percentofasymptomaticbacteriuria.Klebsiellapneumoniea,Proteusspecies,staphylococcalspecies,enterococci,andgroupBstreptococcicanalsoestablishcolonization.
506.Tocreateanaerobiosiswhichorganism isused a)Micrococcus b)Clostridium c)B.anthracis d)Corynebacterium CorrectAnswer-AAns.is'a'i.e.,MicrococcusObligateaerobicmicrococcusisusedtocreateanaerobiccondition(anaerobiosis).Themicrococcusandtheanaerobicorganismtobecultivatedarebothinoculatedintothesameliquidmedium.DuringincubationtheMicrococcusgraduallyutilizesthefreeoxygencreatingconditionsfavorableforthegrowthofanaerobe.Afteranaerobiosisisachieved,themicrococcusdies(duetolackofoxygen)leavingtheanaerobeinpureculture.
507.A30yearsoldmaleishavingprpductive coughwithdysnea.Bloodgasanalysisshowslowpa02.Chestx-rayisshowingreticulonodularpattern.Thecausativeagentis? a)Staphaureus b)Pneumococcus c)P.jerovecii d)Pseudomonas CorrectAnswer-CAns.is'c'i.e.,P.jerovecii[RefReadbelow]Reticulo-nodularshadowisseenininterstitialpneumonia.AmongthegivenoptionsPjeroveciiisacauseofinterstitialpneumonia.Otherthreeoptionsarecausesofairspacepneumonia."PneumocystisCariniipneumoniaproducesadiffuse,symmetric,fine-to-mediumreticulonodularpattern".
508.Whichofthefollowingisamethodof Pasteurization a)Vatmethod b)Pasteurmethod c)Billingmethod d)Flashmethod CorrectAnswer-A:DAns.is'a&d'i.e.,Vatmethod&Flashmethod[RefPark23ra/ep.655]Pasteurizationisdonetodestroythepathogensinmilk.Itkillsnearly90%ofbacteriainmilk,includingmoreheatresistanttubercularbacilliandQ-feverorganism.However,thermoduricbacteriaandsporesarenotkilled.Therearefollowingmethodsofpasteurization:?A)Holdermethod(Vatmethod)Milkiskeptat63-66?Cfor30minutesandthenrapidlycooledto5?C.B)Hightemperatureshorttime(HTST)methodItisalsocalledFlashmethod.Milkisheatedto72?Cfor15secondsandthenrapidlycooledto4?C.Itisnowthemostwidelyusedmethod.C)Ultra-hightemperature(UHT)methodMilkisrapidlyheatedintwostagesto125?Cforfewseconds,2"dstagebeingunderpressure.Itisthenrapidlycooled. Method Remarks Holder/Vat Forsmallandrural Method communities HTST(flash) Mostwidelyused,forlarge
HTST(flash) Mostwidelyused,forlarge Method quantitiesHeatingin2stages UHTMethod 2'dstageunderpressure
509.TemperatureusedinTyndallizaton a)40?C b)60?C c)80?C d)100?C CorrectAnswer-DAns.is'd'i.e.,100?C[RefAnanthanarayan9thiep.31&triep.33]Tyndallization(intermittentsterilization)Mediacontainingsugarorgelatinaresterilizedbyheatingat100?Cfor20minutesonthreesuccessivedays.Firstexposurekillsallvegetativebacteria.Sporesgerminateandarekilledonsubsequentexposures
510.Nutrientagarheatedat80?Cusedfor a)Sporegermination b)Togrowmesophilicbacteria c)Togrowthermophilicbacteria d)Forclostridiumisolation CorrectAnswer-A:DAns.is'a'>'d'i.e.,Sporegermination>ForclostridiumisolationHeatingfor20minutesat80degreescentigradedestroysvegetativecellsandactivatesthesporesforgermination.Thismethodcanbeusedtocultivateanaerobicspore-formingorganisms(e.g.clostridium)Aboutoptionsa&cMicroorganismscanbegroupedintobroad(butnotveryprecise)categories,accordingtotheirtemperaturerangesforgrowth.Psychrophiles(cold-loving)cangrowat0?C,andsomeevenaslowas-10?C;theirupperlimitisoftenabout25?C.Mesophllesgrowinthemoderatetemperaturerange,fromabout20?C(orlower)to45?C.Thermophilesareheat-loving,withanoptimumgrowthtemperatureof50?ormore,amaximumofupto70?Cormore,andaminimumofabout20?C.Hyperthermophileshaveanoptimumabove75?Candthuscangrowatthehighesttemperaturestoleratedbyanyorganism.AnextremeexampleisthegenusPyrodictium,foundongeothermallyheatedareasoftheseabed.Ithasatemperatureminimumof82?,anoptimumof105?andagrowthmaximumof110?C.
511.Involutionalformareseeninwhich phaseofbacterialgrowth a)Lagphase b)Logphase c)Stationaryphase d)Deathphase CorrectAnswer-DAns.is'd'i.e.,Deathphase[RefAnanthanarayan94Vep.22]Bacterialgrowthisthedivisionofonebacteriumintotwodaughtercellsinaprocesscalledbinaryfission.Providingnomutationaleventoccurs,theresultingdaughtercellsaregeneticallyidenticaltotheoriginalcell.Hence"Localdoubling"ofthebacterialpopulationoccurs.Bacteriahaveadistinctpatternofgrowthwhenabacteriumisseededintoasuitableliquidmediumandincubated,itsgrowthfollowsadefinitecourse.
512.Apatientispresentingwithrecurrent staphylococcalinfection,kyphoscoliosisandtypicalfaces.Thepatientissufferingfrom? a)IgAdeficiency b)HyperIgEsyndrome c)Commonvariableimmunodeficiency d)Burton'sAgammaglobulinemia CorrectAnswer-BAns.is'b'i.e.,HyperIgEsyndromeJob'ssyndrome(Hyper-IgEsyndrome)Job'ssyndrome,alsocalledHyper-IgEsyndromeorHyperimmunoglobulinEsyndrome,isanautosomaldominantdisorderduetomutationsinSignalTransducerandActivatorofTranscription-3(STAT-3).Thereisdefectinphagocytosis.IgElevelsareelevated.Otherimmunoglobulinsarenormal.Clinicalmanifestationsincludestaphylococcalcoldabscess,otitismedia,recurrentsinopulmonaryandskininfections,andcavitarypneumoniawithpneumatoceles.Besideinfections,otherfindingsarecharacteristicfacieswithbroodnose,osteoporosis,kyphoscoliosis,cerebral.
513.Partialacidfastorganismis a)M.tuberculosis b)M.Bovis c)Nocardia d)None CorrectAnswer-CAns.is'c'i.e.,Nocardia[RefConciseReviewofmicrobiologyp.13]Portialacidfastmeans,organismwhichisshowslessaffinityforprimarystain,thuslessconcentratedH2So4(insteadof20%H2So4)isusedfordecolorizationofprimarystain(Carbolfuschin).PartialacidfastbacteriaareMleprae(5%H,SO4),andNocardia(0.5%H2SO4)
514.Resolvingpowerofelectronmicroscope a)1-5mm b)1-5um c)1-5nm d)1-5A? CorrectAnswer-DAns.is'd'i.e.,1-5Ae[RefEssentialsofmedicalmicrobiology]
515.Mosteffectiveantibodyforprecipitation ? a)IgM b)IgG c)IgA d)IgD CorrectAnswer-BAns.is'b'i.e.,IgG[RefHarrison19th/ep.372&18th/ep.2674;Ananthanarayan9thiep.98&8th/ep.98]IgMismoreeffectivethanIgGfor: 1. Immunehemolysis2. Opsonization3. Complementfixationbyclassicalpathway4. Bacterialagglutination IgGismoreeffectivethanIgMfor: 1. Neutralizationoftoxins&viruses2. Precipitationreactions.
516.Specificityofantibodyisdependenton? a)Fcportion b)Fabregion c)Carboxyterminal d)Alloftheabove CorrectAnswer-BAns.is'b'i.e.,Fabregion[Ref:Harrison19th/ep.372;Ananthanarayan9thiep.100]TheinfiniterangeoftheantibodyspecificityofimmunoglobulinsdependsonthevariabilityoftheaminoacidsequencesatthevariableunitsofHandLchains.VariableregionispresentonFabregion.
517.Classificationofstaphylococcusis basedon- a)Catalasetest b)Coagulasetest c)Mannitolfermentation d)Optochinsensitivity CorrectAnswer-BAns.is'b'i.e.,CoagulasetestMedicallyimportantstaphylococcithatcausehumandiseasearedividedintotwogroups:?Coagulasepositive:Staphylococcusaureus.Coagulase-negative:Staphylococcusepidermidis,Staphylococcushaemolyticus,Staphylococcussaprophyticus.
518.Antibodyspecificityisdueto? a)AminoacidsequenceatHchain b)AminoacidsequenceatLchain c)Aminoacidatcarboxyterminal d)Aminoacidsequenceattheaminoterminal CorrectAnswer-A:B:DAns.is'd>a&b'i.e.,Aminoacidsequenceataminoterminal>AminoacidsequenceatHchain&AminoacidsequenceatLchain[RefReadbelow]Antibodyspecificityisduetovariabilityoftheaminoacidsequencesatthevariableunit(ataminoterminal)ofbothHandLchains(notonlyHorLchains).
519.Ironhelpsinvirulenceofwhich organism a)Streptococcuspyogenes b)Pneumococcus c)Staphylococcusaureus d)Pseudomonas CorrectAnswer-CAns.is'c'i.e.,StaphylococcusaureusStaphylococcusaureuscausesasignificantamountofhumanmorbidityandmortality.TheabilityofS.aureustocausediseaseisdependentuponitsacquisitionofironfromthehost.S.aureuscanobtainironfromvarioussourcesduringinfection,includinghaemandtransferrin.Themostabundantironsourceinhumansishaemironboundbyhaemoglobincontainedwithinerythrocytes.S.aureusisknowntolyreerythrocytesthroughsecretionofpore-formingtoxins,providingaccesstohosthaemoglobin.Proteinsoftheiron-regulatedsurfacedeterminant(Isd)systembindhosthemoproteins,removethehaemcofactor,andshuttlehaemintothecytoplasmforuseasanutrientironsource.DeletionofIsdsystemcomponentsdecreasesstaphylococcalvirulence,underscoringtheimportanceofhaemironacquisitionduringinfection.Inadditiontohaem,S.aureuscanutilizetransferrinironthroughthesecretionofsiderophores.Severalstaphylococcalsiderophoreshavebeendescribed,someofwhichhavedefinedrolesduringthepathogenesisofstaphylococcal
infections.
520.Wool-Sorterdiseaseiscausedby a)Pseudomonas b)Bacillusanthracis c)Vibrioparahemolyticus d)Spirillusminor CorrectAnswer-BAns.is'b'i.e.,Bacillusanthracis[RefHarrison19(h/ep.261;Ananthnarayan/ep.246]BacillusAnthracisisthecausativeorganismofanthrax.Inhuman,anthraxoccursinfollowingforms?Cutaneousanthrax(Hideporter'sdisease)Itisthemostcommonformofanthrax.Itisapainlesslesionandiscalledcharbonormalignantpustule.Itgenerallyresolvesspontaneously,but10-20%ofuntreatedpatientsmaydevelopfatalsepticemia.Pulmonaryanthrax(Woolsorter'sdisease)Itfollowsinhalationofdustfrominfectedwool.Itpresentsashemorrhagicpneumonia.Intestinalanthraxisrarestform.
521.NottrueaboutsporothrixSchenckii? a)Dimorphicfungus b)Asteroidbodies c)Copperpennybodies d)Commoningardners CorrectAnswer-CAns.is'c'i.e.,Copperpennybodies[RefHarrison19th/ep.1353]Copperpennybodiesareseeninchromoblastomycosis.SporothrixSchenckiiSporothrixSchenckiiisadimorphicfungus.Theorganism(sporothrixschenckii)areusuallydescribedastiny,cigar-shapedbodies,3-5micronsinlength,whichbearfromonetothreesmallovalbudsateitherorbothpales.Occasionallyalargerasteroidbodymaybeseen.BecauseS.schenckiinaturallyfoundinsoil,hay,sphagnummoss,andplants,itusuallyaffectsfarmers,gardeners,andagriculturalworkers.Thisfungaldiseaseusuallyaffectstheskinalthoughrareformscanaffectthelungs,joints,bonesandCNS.Fungusentersthroughsmallcutsandabrasionsintheskintocausetheinfection.Becauserosescanspreadthedisease,itisoneofafewdiseasesreferredtoasrose-thornorrosegardener'sdisease.
522.Fishyodourisfoundongrowthofwhich organism a)Proteus b)Pseudomonas c)Yersiniapseudotuberculosis d)Yersiniapestis CorrectAnswer-AAns.is'a'i.e.,ProteusProteusispartofthenormalfloraofthehumangastrointestinaltract.Itcanalsobefoundfree-livinginwaterandsoil.Whenthisorganism,however,enterstheurinarytract,wounds,orthelungsitcanbecomepathogenicCultureofproteusbacillihasacharacteristicputrefactiveodordescribedas'fishyorseminal".Rottencookedfishyodor:Proteusmirabilisproducesaverydistinctfishyodor.OnSalmonella-Shigella(SS)agar,Proteususuallysmellslike"rottencookedfish".
523.Lipophilicfungusis? a)Malasseziafurfur b)Candida c)Cryptococcus d)Histoplasma CorrectAnswer-AAns.is'a'i.e.,Malasseziafurfur[RefPrinciplesofmedicalmicrobiologyp.781]Malasseziafurfur(Pityrosporumovale)isalipopphilicfungusthatisfoundinareasofthebodythatarerichinsebaceousglands.Thisfunguscausestineaversicolor(pityriasisversicolor).
524.A60yearsoldfarmerhasdeveloped swellingonthesoleoffootwithdischargingyellowgranules.Thediagnosisis- a)Fungalmycetoma b)Eumycetoma c)Actinomycosis d)Candidiasis CorrectAnswer-CAns.is'c'i.e.,ActinomycosisMycetomaIsalocalizedchronicgranulomatousinvolvementofthesubcutaneousanddeepertissues,commonlyaffectingthefootandlessoftenthehandandotherparts.Presentingasasubcutaneousswellingwithmultipledischargingsinuses.Sinusesdischargeseropurulentfluidcontaininggranules.Thesegranulesaremicrocoloniesoftheetiologicalagents.Mycetomacanbecausedbybothfungusandbacteria
525.Rapiddetectionofmeningococal meningitisis a)Bloodculture b)CSFculture c)PCR d)None CorrectAnswer-CAns.is'c'i.e.,PCR[RefBasicinmicrobiologyp.719]"PCRassaycanbeperformedrapidlywithaturnaroundtimeof2hourfromintiationofDNAextractiontotheissuingofreports".LaboratorydiagnosisofmeningococciSpecimensusedareCSF(forcases),nasopharyngealswab(forcarrier),blood(inmeningococcemia&earlymeningitis),andpetechiallesions(inmeningococcemia).Bestspecimenforcase4CSF(bylumbarpuncture).Bestspecimenforcarrier4Naspharyngealswab.
526.Presumptivediagnosisof meningococcalmeningitisismadeearliestby- a)CSFculture b)PCR c)Latexagglutination d)CFT CorrectAnswer-CAns.is'c'i.e.,Latexagglutination[RefEssentialsofmedicalmicrobiologyr3d/ep.412]IncombinationwithaclinicalpictureCSFexaminationconsistentwithbacterialmeningitis,apresumptivediagnosisofbacterialmeningitiscausedbyN.meningitidis,S.pneumoniae,orH.influenzaecanbymadeafterperformingaGramstainoftheCSFsedimentorbydetectionofspecificantigensintheCSFbyalatexagglutinationtestorusingRDTs.Positiveresultsforanyofthesetestscanrapidlyprovideevidenceofinfectionevenifculturesfailtogrow.PCRandCSFcultureareusedfordefinitivediagnosis(notpresumptivediagnosis)
527.Chlamydosporeisformedby? a)Candidaalbicans b)Candidapscitasi c)Histoplasma d)Cryptococcus CorrectAnswer-AAns.is'a'i.e.,Candidaalbicans[RefAnanthanarayan8thlep.607-608]Allcandidaspeciespathogenicforhumansarealsoencounteredascommensalsofhumans,particularlyinthemouth,stoolandvagina.Theygrowrapidlyonsimplemediaasovalbuddingcellsat25?to37?C.Intissue,bothyeastsandpseudohyphaearepresent.Candidaalbicansisdifferentiatedbyothercandida:Itformstruehyphae(mycelia)orgermtubeswhengrowninserum.Itformsthickwalledlargesporescalledchlamydosporeswhengrownincornmealagar.Itisdimorphic.
528.Sewerswabsaretakentodetect a)Typhoidcasesincommunity b)Choleracasesincommunity c)Typhoidcarriersincommunity d)Choleracarriersincommunity CorrectAnswer-CAns.is'c'i.e.,Typhoidcarriersincommunity[RefTextbookofpracticalMicrobiologyp.721]TyphoidcarriersaredetectedbySewer-swabmethod'.Theuseofsewerswabsenablespremisestobescreenedforthepossibilityoftheexistenceofasalmonellaproblemmorequicklyandmoreeasilythanbytheexaminationofmanyend-of-linesamples.Intheeventofsalmonellaebeingfound,areturnvisitcanbepaidanddetailedsamplestakentoattempttodefectthesourceofcontamination.
529.Aspergillusfumigatusisdifferentiatedby otherfungiby? a)Showingseptatehyphae b)Growat45?C c)Causerespiratorytractinfection d)Mostcommonendemicmycosis CorrectAnswer-BAns.is'b'i.e.,Growat45?C[RefHarrison19thiep.1346;Ananthanarayan8th/ep.613]Aspergillusisamouldwithseptatebranchinghyphae.AbilityofA.fumigatustogrowat45?Chelpstodistinguishitfromotherspecies.Modeoftransmission-InhalationofAspergillusspores(Conidia)intolungs.Thecommonesthumandiseasecausedbyaspergillusisotomycosis.Aspergillusinfectioninneutropenicpatientischaracterizedbyhyphalinvasionofbloodvessels,thrombosis,necrosisandhemorrhagicinfarction
530.Speciesofshigellacausingarthritis a)Shdysenteriae-1 b)Shsonnei c)Shflexneri d)Shboydii CorrectAnswer-CAns.is'c'i.e.,Shflexneri[RefHarrison18th/ep.945]Shigellaishighlycommunicable.Theinfectivedoseforshigellaisless.Itcanbeaslowas10-100bacillibecausetheysurvivegastricaciditybetterthanotherenterobacteriae.Shigellaeproducefollwingclinicalfeatures.1)Intestinal:Theseare:-Dysentery:MostcommoncauseisShdyenteriaetypel.Diarrhea:UsuallybyShSonnei.2)Extraintestinal:Thesearehemolyticuremicsyndrome(causedbyShdysenteriae-I),arthritis(Shflexneri),seizures(Shflexneri),pneumoniaandReitersyndrome(inHLAB27association).
531.Ectothrixiscausedby? a)Ttansurans b)Tviolaceum c)Microsporumcanis d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,Microsporumcanis[Ref:Greenwood16thiep.574]Tineacapitisisdermatophyticinfectionofscalpandscalphair.Occurscommonlyinchildren.Itisuncommoninadults(incontrast,T.crusis,T.manuumandT.unguiumarecommoninadults).Causedbygeneratrichophytonormicrosporum.Asepidermophytondoesnotaffectthehair,EpidermophytondoesnotcauseT.capitis.TwomostcommonspeciescausingT-CapitisareM.canis&T.tonsurans.Tineacapitismaybetwotypes. 1. EndothrixInvasionofhairshaftbyfungus.Itiscausedby T.tonsurans(MC),T.violaceum,T.schoenleinii. 2. EctothrixFungalinvasionisrestrictedtotheoutermostcuticleof hair.ItiscausedbyM.canis(MC),M.audouini,T.mentagrophytes.AsectothrixisthecommonesttypeofT.capitis,MicrosporumcanisisthemostcommoncauseofT.Capitis
532.Griffthclassificationisbaseon a)'C'-carbohydrate b)M,T,Rantigens c)Typeofhemolysis d)0,requirment CorrectAnswer-BAns.is'b'i.e.,M,T,Rantigens[RefAnanthanarayan9th/ep.209,210]Group'A'strep.arefurthersubdividedintotypesbasedontheprotein(M,TandR)antigenspresentonthecellsurface(Griffithtyping).About80typesofstr.pyogeneshavebeenrecognized.
533.Sabouraud'sdextrose[glucose]agaris usedforisolationof- a)Pseudomonas b)B.Antracis c)Fungi d)Ancylostome CorrectAnswer-CAns.is'c'i.e.,Fungi[RefGreenwood10/ep.570;Ananthanarayan8th/ep.601]Culturemediausedinmycologyare: 1. Sabouraud'sglucoseagar(mostcommon)2. Czapek-Doxmedium3. Cornmealagar
534.Similaritybetweenchlamydiaandvirus is a)Filterablethroughfilter b)Abilitytogrowincellfreemedia c)ContainsbothDNAandRNA d)Alloftheabove CorrectAnswer-AAns.is'a'i.e.,Filterablethroughfilter[RefTextbookofmicrobiologybyParijap.418]Chlamydiaewerethoughttobevirusesbecause(likeviruses)they:Passthrough0.45ymfilters.Areobligateintracellularparasite-cannotbegrownincellfreemedia.
535.BloodydiarrheainHIVinfectedpatientis mostlydueto? a)Cryptosporidium b)Isospora c)CMV d)Salmonella CorrectAnswer-CAns.is'c'i.e.,CMV[Refwww.medscape.com]ThemostcommonoftheopportunisticinfectionsthatcausediarrheainpatientswithAIDSareCMVinfection,cryptosporidiosis,microsporidiosis,andMACinfection.CMVinfectionisthemostcommonopportunisticviralinfectionintheGItractofHIV-infectedpatientsandcancauseproblemsfromthemouthtotheanus.Itmostfrequentlycausesacolitisassociatedwithfever,crampyabdominalpain,andfrequent(oftenbloody)stools.
536.Whichtestcannotdifferentiateendemic andepidemictyphus a)Weil-Felixreaction b)Complementfixationtest c)Immunofluorescence d)Radioprecipitation CorrectAnswer-AAns.is'a'i.e.,Weil-FelixreactionBothepidemictyphusandendemictyphusarepositiveforOX-19antigenThusWeilFelixreactioncannotdifferentiatebetweenthetwo.Weil-FelixreactionThisreactionisanagglutinationtestinwhichseraaretestedforagglutininsto0antigensofcertainnonmotileproteusstrainsOX-19,OX-2andOX-K.Thebasisofthetestisthesharingofanalkali-stablecarbohydrateantigenbysomerickettsiaeandbycertainstrainsofproteus,P.vulgarisOX-19andOX-2andP.mirabilisOX-K.Thetestisusuallydoneasatubeagglutination,thoughrapidslideagglutinationmethodshavebeenemployedforscreening.
537.CCR5mutationisrelatedtowhich condition? a)ResistancetoHIVinfection b)SusceptibilitytoHIVinfection c)ResistancetoHBVinfection d)SusceptibilitytoHBVinfection CorrectAnswer-AAns.is'a'i.e.,ResistancetoHIVinfection[Refwww.lumenlearning.com]Inrecentyears,scientificinteresthasbeenpiquedbythediscoveryofafewindividualsfromnorthernEuropewhoareresistanttoHIVinfectionin1998,AmericangeneticistStephenJ.O'BrienattheNationalInstitutesofHealth(NIH)andcolleaguespublishedtheresultoftheirgeneticanalysisofmorethan4,000individuals.TheseindicatedthatmanyindividualsofEurasiandescent(upto14%insomeethnicgroups)haveadeletionmutation,calledCCR5delta32,inthegeneencodingCCR5isacoreceptorfoundonthesurfaceofTcellsthatisnecessaryformanystrainsofthevirustoenterthehostcell.ThemutationleadstotheproductionofareceptortowhichHIVcannoteffectivelybindandthusblocksviralpeoplehomozygousforthismutationhavegreatlyreducedsusceptibilitytoHIVinfection,andthosewhoareheterozygoushavesomeprotectionfrominfectionaswell.
538.E.colisubtypesaredividedonthebasis of a)Lactosefermentation b)Virulenceproperties c)Somatic0antigen d)Maltosefermentation CorrectAnswer-BAns.is'b'i.e.,Virulenceproperties[Refenwikipedia.org]EntericE.coli(EC)areclassifiedonthebasisofserologicalcharacteristicsandvirulenceproperties:?EnteropathogenicE.coli(EnteroadherentEcoli)EnterohemorrhagicE.coliorverotoxigenicE.coliEnterotoxigenicE.coliEnteroaggregativeE.coliEnteroinvasiveE.coli
539.Trueaboutrhabdoviridaeareallexcept? a)Includesvesculostomatitisvirus b)Rabiesvirusisinactivatedbyformalin c)RabiesvirusisnegativesensedoublestrandedRNAvirus d)Alloftheabovecorrect CorrectAnswer-CAns.is'c'i.e.,RabiesvirusisnegativesensedoublestrandedRNAvirusRhabdoviridaecontainstwogenera:? 1. Vesiculoviruses:Vesculostomatitisvirus,chandipuravirus.2. Lyssavirus:Rabiesvirus. RabiesvirusItisaneneveloped,RNA(negativesensessRNA)virus.IthasRNAdependentRNApolymerase.Itisabulletshapedvirus.Rabiesvirusissensitivetoethanol,iodinepreparations,soap,quaternaryammoniumcompound,detergentsandlipidsolvents(likeether,chloroform).Itisinactivatedbyphenol,beta-propiolactone(BPL),formalin,Sunlight,UVirradiation,andbyheat.Rabiesisprimarilyazoonoticdiseaseofwarm-bloodedanimals,particularlycarnivoroussuchasdogs,Cats,Jackalsandwolves.Itistransmittedtomanusuallybybitesorlicksofrabidanimals.Itisthecommunicablediseasewhichisalwaysfatal.Itisdeadendinfectioninman.
540.ELISAtestforvirulenceantigenisused forwhichtypeofEcoli a)ETEC b)EIEC c)EHEC d)EAEC CorrectAnswer-BAns.is'b'i.e.,EIEC[RefAnanthnarayan9th/ep.279]ForlaboratorydiagnosisofEIEC,theSerenytestusedtobeemployed(thatis,instillationofsuspensionoffreshlyisolatedEIECorshigellaintotheeyesofguineapigsleadstomucopurulentconjunctivitiesandseverekeratitis).Micemaybeusedinsteadofguineapigs.CellpenetrationofHeLaorHEP-2cellsincultureisamorehumanediagnostictest.Thisabilitytopenetratecellsisdeterminedbyalargeplasmid,detectionofwhichcanalsobeadiagnostictest.Theplasmidcodesforoutermembraneantigenscalledthe'virulencemarkerantigens'(VMA)whichcanbedetectedbytheELISA(VMAELISA)test.
541.E.coliinfectionoccurinwhichenzyme defect a)Lactase b)Pyruvatekinase c)Pepsin d)Trypsin CorrectAnswer-BAns.is'b'i.e.,Pyruvatekinase[RefHardcoremicrobiology&immunologybyBenjaminWSearsp.133]Opportunisticinfectionsisimmunodeficiencyduetodefectinmyeloidcellsare:-StaphaureusKlebsiellaPneumococcusE.coliNeisseriaCandidaConditionscausingdefectinmyeloidcellsare:?ChronicgranulomatousdiseaseChediak-HigashisyndromeG6PDandpyruvatekinasedeficiencyMyeloperoxidasedeficiency
542.Culturemediacontainingpotassium tellurite a)TCBSmedium b)Monsurmedium c)BYCEmedium d)MullerHintonagar CorrectAnswer-BAns.is'b'i.e.,Monsurmedium[RefFundamentalprinciplesofbacteriologyp.129]Monsur'sGTTAmediumisMonsur'sgelatintourocholatetrypticasetelluriteagar.SelectivemediaforvibriocholaraeTCBSmedium(pH8.6):Thismediumcontainsthiosulfate,citrate,bilesalts,sucrose,andbromothymolblue(indicator).V.choleraeproduceslarge,yellowconvexcoloniesonthismedium.Thisisduetofermentationofsucrosebythebacteria,leadingtoproductionofacid.AccumulationofacidreducespHofthemedium,andsothecolorofthebromothymolblueindicatorbecomesyellow,thusmakingV.choleraecoloniesyellow.Nonsucrose-fermentingV.parahaemolyricusproducesbluegreencolonies.Monsur'sGTTAmedium(pH8.5):HighpHofthemediumandpresenceofpotassiumtelluriteinthismediuminhibitsmostofGrampositivebacteriaandentericbacteriawithexceptionofproteusspecies.Hence,theGTTAmediumisusedforisolationofV.choleraeandothervibriosfromfeces.V.choleraeproducessmalltranslucentcolonieswithgrayishblackcencerandaturbidhaloafter24hoursofincubation.Thecoloniesbecomelarger(3-4mminsize)afteraprolongedincubationof48hours.
AlkalineBSA(pH8.2):ThisisanotherselectivemediumusedforV.cholerae.ThecoloniesonBSAaresimilartothoseonnutrientagar.
543.Borreliacauseswhichofthefollowing a)Weil'sdisease b)Bejels c)Vincentangina d)Yaws CorrectAnswer-CAns.is'c'i.e.,VincentanginaThreeimportantdiseasescausedbyBorreliaeare:?Lymedisease:CausedbyB.burgdorferiRelapsingfever:CausedbyB.recurrentis,Bduttoni,B.hermsii,B.Parkeri,B.turicatae,B.persica,B.hispanica.Vincent'sangina:CausedbyB.vincenti.
544.Zikaviruscauses? a)Hepatitis b)Myocarditis c)Conjunctivitis d)Noneofthese CorrectAnswer-CAns.is'c'i.e.,ConjunctivitisZikavirus(ZIKV)isaflavivirusrelatedtoyellowfevervirus.ItistransmittedbyAedesmosquito.Zikavirusdisease(Zika)isadiseasecausedbytheZikavirus,whichisspreadtopeopleprimarilythroughthebiteofaninfected
545.Whatissimilarbetweenrotavirusand Norwalkvirus? a)Bothbelongtosamefamily b)Bothhavesegmentedgenome c)BothhavesinglestrandedRNA d)Botharecausesofviralgastroenteritis CorrectAnswer-DAns.is'd'i.e.,Botharecausesofviralgastroenteritis[RefEssentialsofMicrobiologyp.497]RotavirusbelongstoreoviridaedoublestrandedsegmentedRNA.NorwalkvirusbelongstocalciviridaeSinglestrandednonsegmentedRNA.BothRotavirusandNorwalkvirusarecausesofviralgastroenteritis
546.Rota-teqoralvaccineforrotavirus contains? a)2reassortedrotaviruses b)3reassortedrotaviruses c)4reassortedrotaviruses d)5reassortedrotaviruses CorrectAnswer-DAns.is'd'i.e.,5reassortedrotaviruses[RefEssentialofmedicalmicrobiologyp.932]Rota-virusvaccineTheRotavirusvaccinesarelive-attenuatedvaccinesgivenorally.Twonewvaccinesarenowinuse- 1. RV5oralpentavalentvaccine(Rotateq)containsfivereassortant rotavirusesdevelopedfrom5humanstrainsonbovinerotavirusbackground[ThesefivestrainsareGI,G2,G3,G4andP(8)] 2. RV1monovalentvaccine(Rotarix)containsoneliveattenuated rotavirusstrain[thestrainisP1A(8)GI]TheadministrationofRotarix(2doses)andRotaTeq(3doses)needstobecompletedby32weeksofagetominimizeanypotentialriskofintussusception.Thefirstlicensedrotavirusvaccine,aRhesusmonkeyrotavirus-basedtetravalenthumanreassortantvaccine(Rotashield),waswithdrawnafterthisliveoralvaccinewasassociatedwithdevelopmentofintestinalintussusception.
547.Coreantigen[HBOinHBVisencloded bywhichgene? a)S b)C c)P d)X CorrectAnswer-BAns.is`b'i.e.,C[RefAnanthanarayan9th/ep.544]ThegenomeofHBVismadeofcircularDNA,butitisunusualbecausetheDNAisnotfullydoublestranded->oneofthestrandsisincompleteandotheriscomplete4partiallydoublestrandedDNA.Therearefourknowngenesencodedbygenome-'C',X','P','S'.Pgeneisthelargestgene..X-genecodesforHBxAg,whichcantransactivatethetranscriptionofcellularandviralgenesandmaycontributetocarcinogenesis.HBxAganditsantibodyarepresentinpatientswithseverechronichepatitisandhepatocellularcarcinoma.
548.WhichofthefollowingisHepadnavirus? a)HAV b)HBV c)HCV d)HDV CorrectAnswer-BAns.is'b'i.e.,HBV[RefAnanthnarayan9th/ep.549&8thlep.545]
549.HSV-2causeslatentinfectioninwhich nerveplexus/ganglia? a)Trigeminalganglion b)Oticganglion c)Sacralganglion d)Ciliaryganglion CorrectAnswer-CAns.is'c'i.e.,Sacralganglion[RefEssentialsofmedicalmicrobiology3'/ep.1215]SiteoflatencyHSV-1Trigeminalganglion.HSV-2Sacralganglion.
550.Handfootmouthdiseaseiscausedby? a)Enterovirus-70 b)Coxsackie-Avirus c)Coxsackie-Bvirus d)Enterovirus CorrectAnswer-BAns.is'b'i.e.,Coxsackie-Avirus[RefGreenwoodle/ep.459;Ananthanarayan9th/ep.491]TherearetwotypesofCoxsackieviruses: 1. CoxsackieA(Seotypes1to24):Theycauseasepticmeningitis (especiallyA7andA9),Herpangina,febrileillness,acutehemorrhagicconjucntivitis(byA24),and'Hand-foot-mouthdisease'. 2. CoxsackieB(Sterotypes1to6):Theycauseasepticmeningitis(all serotypes),neonataldisease,Bornholmdisease(plurodyniaorepidemicmyalgia),myocarditis,hepatitis,pancreatitis&DM(serotypeB4),andpneumonia.
551.Allvirusesareassociatedwithspecific inclusionbody,except? a)CMV b)Malluscumcontagiosum c)EBV d)Yellowfever CorrectAnswer-CAns.is'c'i.e.,EBV[RefEssentialsofmedicalmicrobiologyp.791]
552.Intermediatehostisnotrequiredfor whichparasite- a)Toxoplasma b)Schistosoma c)Ancylostoma d)Fishtapeworm CorrectAnswer-CAns.is'c'i.e.,Ancylostoma[RefRajeshKarykartep.7]Thesequentialstagesingrowth,developmentandmultiplicationconstituteitslifecycle
553.GenerationtimeforMtuberculosis a)10-15min b)10-15hours c)10-15days d)5-10days CorrectAnswer-BAns.is'b'i.e.,10-15hours[RefAnanthanarayan8th/ep.365]Generationtimeofleprabacillus412-13daysGenerationtimeoftuberclebacillus14hoursGenerationtimeofcoliformbacilli20minutes
554.Maurer'sdotsareseeninwhichspecies ofplasmodium? a)Povale b)Pvivax c)Pfalciparum d)Pmalariae CorrectAnswer-CAns.is'c'i.e.,P.falciparum[RefChatterjee12th/ep.79-80] P.vivax Schuffner'sdot P.malariae Ziemann'sstippling,P.falciparum Maurer'sdotP.ovale Schuffner'sdot
555.WhichstageofLeishmaniaisfoundin spleenaspirateofpatient? a)Amastigote b)Promastigote c)Epimastigote d)Trypomastigote CorrectAnswer-AAns.is'a'i.e.,Amastigote[RefEssentialsofparasitologyp.122]Amastigoteforms,alsoknownasLeishmaniadonovanibodies,arefoundintracellularlyintissueslikeliver,spleenandbonemarrow.ApositivebonemarroworspleenaspirationforL.donovanibodiesprovidesconfirmationofdiagnosis.
556.AdherenceofE.histolyticatocolonic mucosaismediatedby? a)Fibronectin b)Lectin c)Collagen d)Fucose CorrectAnswer-BAns.is'b'i.e.,Lectin[Refwww.pathologyoutlines.com]PathophysiologyofE.histolyticainfectionCystareingestedfromfecallycontaminatedfoodorwater,sexualtransmissionalsooccurs.Excystationto8motiletrophozoitesoccursinthesmallintestineThecystsareresistanttogastricacid(andchlorineinwatersupplies).Trophozoitesarepotentiallyinvasiveandmultiplybybinaryfission.Inanestimated20%ofinfectionsinvasionintothewallofthecolonwithtissuedestructionoccurs.AdherencetocolonicmucosaismediatedbyalectinonE.histolytics'ssurface.TheparasitetheninducesapoptosisofepithelialcellsthroughachannelformingporeproteinE.histolyticaingestsremnantcells.Sometrophozoitesundergoencystationthroughsignallingpathwayscompletingthecycle.
557.Pulmonaryeosinophiliaisfoundin infectionwith? a)Babesia b)Malaria c)Strongyloides d)Trypanosoma CorrectAnswer-CAns.is'c'i.e.,Strongyloides[RefHarrison18th/ep.2120&17th/ep.1610]AscarisStrongyloidesstercoralisAncylostoma(hookworm)WuchereriabancroftiorW.malayiToxocara
558.Cystwithscolexandhooksisseenin a)T.saginatu b)Fishtapeworm c)Echinococcus d)H.diminuta CorrectAnswer-CAns.is'c'i.e.,Echinococcus[Ref:Clinicalparasitology3rd/ep.315]Firstonemustunderstandthemeaningofscolex.Scolexispear-shapedorknoblikeheadofcystodes(tapeworms).Scolexiscoveredwithsuckersandhooks:- 1. Taeniasolium:Scolexcontainsfoursuckersandrostellarhooks (rostellumwithhooks). 2. Taeniasaginata:Scolexcontainsfoursuckersbutno hooks/rostellum(hookless). 3. H.Nana:Scolexcontainsfoursuckersandrostellumofhooks.4. H.diminuta:Scolexcontainsfoursuckersbutnohooks(hookless).5. Echinococcus:Scolexcontainssuckersandrostellumofhooks.6. Diphyllobothriumlotus:Scolexhastwoelongatedsuckinggrooves (insteadofsuckers).Therearenohooks(hookless).
559.E.coliisdifferentiatedbyEhistolytica bypresenceof a)Veryactivemovement b)Thinnuclearmembrane c)Cystwith1-4nuclei d)Bluntpseudopodia CorrectAnswer-DAns.is'd'i.e.,Bluntpseudopodia[Ref:Essentialsofmedicalparasitologyp.37]
560.Exampleoftransferofdrugresistance byconjugation- a)Staphylococcitorifampicin b)PneumococcustopenicillinG c)Mtuberculosistoantituberculardrugs d)Ecolitostreptomycin CorrectAnswer-DAns.is'd'i.e.,Ecolitostreptomycin[RefBasicsinlaboratorymicrobiologyp.781]DrugresistanceItreferstounresponsivenessofamicroorganismtoanantimicrobial.Drugresistancemaybeacquiredby:1.MutationItmaybesinglestep(entercoccitostreptomycine,staphlococcitorifampicin)ormultistep(erythromycin,tetracycline,chloramphenicol,salmonellaforciproflaxacin).Mutationaldrugresistanceisalsoimportantintuberculosis.2.GenetictransferDrugresistancefromoneorganismtoothermaybetransferredby:Conjugation(mostcommon):Itisresponsibleformultidrugresistance.ItisimportantforresistanceofS.typhiagainstchloramphenicolandE.coliagainststreptomycin.Transduction:Mostimportantfortransferofresistanceinstaphylococciby(3?lactamase.Transformation(lesssignificant):ImportantinpneumococciresistancetopenicillinG
561.Shadowcastingisusedin- a)Lightmicroscopy b)Electronmicroscopy c)Opticalmicroscopy d)Fluoroscencemicrospopy CorrectAnswer-BAns.is'b'i.e.,Electronmicroscopy[RefCellandmolecularbiologyp.726]Twostandardmethodsofstaininginelectronmicroscopyare: 1. Shadowcasting2. Negativestaining
562.Frozenphenomenonisusedfor- a)Sterilizationofheatsensitivematerial b)Killingthermophilicbacteria c)Preservationofmicroorganisms d)Stimulatingmetabolismofmicroorganism CorrectAnswer-CAns.is'c'i.e.,Preservationofmicroorganisms[RefMicrobiologyApplicationBasedApproachp.189]Somepsychrophilicbacteriacangrowat0?C,butsubzerotemperatureswillinhibitthemetabolismofmicroorganismingeneral.Freezingiscommonlyusedtopreservefoods,drugsandlaboratoryspecimensbecauseiteffectivelystopsmicrobialgrowth.However,subzerotemperaturemaynotkillmicroorganism(especiallypsychrophilic)andmayinfactpreservethemalongwiththematerialbeingfrozen.Thisphenomenonhasbeenusedbymicrobiologiststostoreandpreservemicroorganisms.
563.Trueaboutuniversalprecautionsareall except- a)Topreventtransmissionofbloodbornepathogens b)Includesuseofhandwashing c)Considerthatallbodyfluidsarecontaminatedwithblood d)Includesuseofglovesandmasks CorrectAnswer-BAns.is'b'i.e.,Includesuseofhandwashing[RefMicrobiologyforsurgicaltechniquesp.796]HandwashingisapartofstandardprecautionsnotuniversalprecautionsUniversalprecautionsUniversalprecautionsisanapproachtoinfectioncontroltotreatallhumanbloodandcertainhumanbodyfluidsasiftheywereknowntobeinfectiouswithHIV,HBVandotherbloodbornepathogens.Bloodbornepathogenstandardrequires.Employeestoobserve'universalprecautions'topreventcontactwithbloodorotherpotentiallyinfectiousmaterial(OPIM)TreatallbloodandOPIMwithproperprecautionslikeuseofgloves,masksandgown.Otherpotentiallyinfectiousmaterialincludes: 1. Bodyfluids:CSF,semen,vaginalsecretion,synovialfluid,pleural fluid,pericardialfluid,peritonealfluid,amnioticfluid,salivaindentalprocedures,anybodyfluidcontaminatedwithblood. 2. Anyunfixedtissueororgan(otherthanskin)fromhuman.3. HIV-containingcells,fluidsorcultures. Universalprecautionshavebeenupdatedintostandardprecautionsthatstateallbodyfluid(exceptsweat)shouldbeconsidered
infectious.
564.Nucleicacidisnotfoundin- a)Virus b)bacteria c)Fungus d)Prions CorrectAnswer-DAns.is'd'i.e.,Prions[RefHarrison19'/ep.451&17th/ep.2647]Prionsareinfectiousparticlewhichcontainsproteinonly.Theydonothavenucleicacid.
565.Oilpaintappearanceonnutrientagaris seenin- a)Streptococcuspyogenes b)Staphylococcusaureus c)Bordtellapertussis d)H.influenzae CorrectAnswer-BAns.is'b'i.e.,StaphylococcusaureusStaphylococcusisfacultativeanaerobe.OptimumpHforgrowthis7.4-7.6andoptimumtemperatureis37?C.Staphaureusproducesgoldenyellowpigment,whichismaximumat22?C.Mostofthestaphylococcusspeciesgrowinthepresenceof10%NaCl
566.Streptococcalpneumoniaepneumonia presentat- a)<5years b)5-15years c)20-25years d)30-40years CorrectAnswer-AAns.is'a'i.e.,<5years[Ref:TextbookofMicrobiologybyParijap.197]Streptococcuspneumoniaeistheleadingcauseofpneumonia,bothlobarandbronchopneumonia.Pneumoniaiscommonattheexteremeofages:Children(especially<5yearsofage)Elderly(>60-65years)Serotypes6,14,18,19and23areresponsibleformostcasesofpneumoniainchildren,whileserotypes1,3,4,7,8and12causepneumoniainadults.
567.Mostcommonagegroupaffectedby streptococcuspyogenes- a)<5years b)5-15years c)20-25years d)30-40years CorrectAnswer-BAns.is'b'i.e.,5-15years[RefParijap.191]Sorethroat(tonsillitis)isthemostcommonmanifestationofstreptococcalinfectionandaffects5-15yearsagegroup.
568.Oropharyngealcommensalwhich predisposestocandidiasis- a)Hemophilusinfluenzae b)Streptococcus c)Staphylococcus d)Lactobacillus CorrectAnswer-BAns.is'b'i.e.,Streptococcus[RefTextbookofpolymicrobialdisease-Chapter18]Anexampleofthecomplexityofcoaggregationmaybetherangeofintergenericcoaggregationsoccuringbetweentheoralfungalpathogencandidaalbicansandotheroralspeciesthatmayplayanimportantroleinthecolonizationoftheoralcavitybycandidaalbicans.Althoughstreptococcalspecies,namely,streptococcusgordonii,streptococcusoralisandstreptococcussanguins,exhibitthehighestaffinitiesforCalbicans,Calbicans(aswellasCandidadubliniensis)havebeenshowntocoaggregatewithFusobacteriumspeciesinsuspension.Actinomyceshasalsobeenshowntocoaggreatewithcandidaalbicans.
569.Hemophilusparainfluenzaerequres- a)FactorV b)FactorX c)FactorV&X d)FactorVII CorrectAnswer-AAns.is'a'i.e.,FactorV[Ref:Ananthanaran9"/ep.327&8thiep.330]H.influenzae,H.aegyptius,H.haemolyticusFactorX&V.H.Parainfluenzae,H.Parahemolyticus,H.ParaphrophilusFactorV.H.ducreyi,H.aphrophilusFactorX.
570.Mostsensitivetestinsyphilis- a)VDRL b)TP-PA c)RPR d)FTA-ABS CorrectAnswer-BAns.is'b'i.e.,TP-PA[RefHarrisonMolep.1137,1138e.718th/ep.1385,Ananthanarayan9th/ep.374,375&p.374-78]TPPAisthemostsensitiveserologicaltestoverall(consideringallstagesofsyphilis).Alltheserologicaltestshave100%sensitivityinsecondarystageofsyphilis Test Primary Secondary Latent Tertiary VDRL/ 78(74- 100 95(88- 71(37- RPR 87) 100) 94) FTA- 84(70- 100 100 96 ABS 100) TP?PA 89 100 100 NA
571.Freshwaterswimmingleadstoinfection by- a)Bordetellapertussis b)Corynebacteriumdiphtheriae c)Mtuberculosis d)Pseudomonas CorrectAnswer-DAns.is`d'i.e.,Pseudomonas[RefAlcamo'sfundamentalsofmicrobiologyp.669]"Extendedswimminginfreshwaterpoolscanirritateandbreakdownskinintheearcanalallowingbacteriasuchaspseudomonas,staphylococcusorstreptococcustopenetrateandcauseotitisexterna"Pseudomonasisthemostcommoncauseofswimmer'searinfection.Pseudomonasalsocauses"hottubrash"syndromeorhot-tubfolliculitis,associatedwithuseofhottub,lesscommonlyassociatedwithwhirlpoolsorswimmingpools.
572.Mostcommoncomplicationofdiphtheria is- a)Myocarditis b)Pneumonia c)Meningitis d)Endocarditis CorrectAnswer-AAns.is'a'i.e.,Myocorditis[RefWithtext]"Myocarditisisthemostcommoncomplicationofdiphtheriaandtheleadingcauseofdeathindiphthericcases,whoseincidenceis10-25%"EssentialsinMicrobiology"Complicationsofdiphtheriaincludemyocarditis(themostcommoncomplication),thrombocytopenia,vocalcardparalysisandneuritis"Clinicalmicrobiology."Mostcommoncomplicationsofdiphtheriaaremyocarditisandtoxicneuritis"NMSTwomostcommoncomplicationsofdiphtheriaare:1.Myocarditis2.ToxinneuritisParalysisofsoftpalateisthemostcommonmanifestationofneuritis.
573.Allaretrueaboutanaerobicinfection except- a)Mostinfectionsareendogenous b)Exudatesandswabsarebestforculture c)SpecimenforUTIissuprapubicaspiration d)TheyarefoundnormallyonskinandGIT CorrectAnswer-BAns.is'b'i.e.,Exudatesandswabsarebestforculture[RefEssentialsofmicrobiologyp.224]Mostanaerobicbacteriathatcauseinfectionaremembersofournormalindigenousfloraandanaerobicinfectionsareusuallyendogenous,causedbytissueinvosionbybacterianormallyresisdentorrespectivebodysurfaces.Anaerobicbacteriaarenormallypresentonskin,mouth,nasopharynx,upperrespiratorytract,gutandvagina.Idealspecimensforanaerobicculturesaresamplesofneedleaspiratesandpropertissuespecimens.Anaerobicswabsareusuallydiscouraged.Importantspecimensare:- 1. Localabscess:Needleaspirates.2. Pulmonary:Transtrachealaspirates,lungaspirates,pleuralfluid, protectedbronchialwash. 3. Abdominal:Abdominalabscessaspirate.4. Urinarytract:Suprapubicbladderaspirate.5. Genitaltract:Culdocentesisspecimen,endometrialswabs.6. CNS:CSF,Aspirateofabscess
574.Mostcommonrouteofinfectionin pasteurellacellulitis- a)Animalbitesorscratches b)Aerosolsordust c)Contaminatedtissue d)Humantohuman CorrectAnswer-AAns.is'a'i.e.,Animalbitesorscratches[RefAnanthanarayan9thlep.325;7h/ep.326;Harrison19thlep.830&le/ep.1235]Transmissiontohumansmayoccurbytworoutes?1)DirectinoculationthroughskinThemostcommonmodeoftransmissionofP.microcidaisdirectinoculationbyabiteorscratch.Mostoftheinfectionsarecausedbycats.Infectionmayalsooccurviadepositionoforganismoninjuredskinormucosalsurfacesduringlicking.2)ThroughtherespiratorytractThisisthesecondmostcommonmodeoftransmission.Infectionviatherespiratorytractoccursfromcontactwithcontaminateddustorinfectiousdroplets(aerosoldust).
575.Non-motilebacteriumis- a)Vibrio b)Clostridiumsepticum c)Clostridiumperfringens d)Legionella CorrectAnswer-CAns.is'c'i.e.,Clostridiumperfringens[RefAnanthanarayan9th/ep.262,263,252-257]AllclostridiaaremotilebyperitrichousflagellaexceptC/tetaniVIandClperfringenswhicharenon-motile.
576.Ehrlichiaphagocytophilamainlyaffects- a)RBC b)Platelets c)Neutrophils d)Macrophages CorrectAnswer-CAns.is'c'i.e.,Neutrophils[RefEssentialsofclinicalmicrobiologyp.712]Anaplasmaphagocytophilum(formerlyknownasEhrlichiaphagocytophila)isacausativeagentoftick-bornefeverinsheepandpasturefeverincattle.Itisanobligateintracellularbacteriumwhosemaintargetisneutrophilsbutitcanalsoinfectmonocytes.
577.Whichviralgeneactsascarcinogenin causingcarcinomacervix- a)P24-gene b)E-gene c)L-gene d)H-gene CorrectAnswer-BAns.is'b'i.e.,E-gene[RefHarrison150/ep.1199-1200]HPVisthemostimportantcauseofcervicalcancer.ProductsofE-genes(E6,E7)arerelatedtoimmortalizationormalignanttransformationofkeratinocytesbyinterferingwithp53andRbgenes,respectively
578.Whichofthefollowingcaninfectovary- a)Mumpsvirus b)EBV c)CMV d)Measlesvirus CorrectAnswer-AAns.is'a'i.e.,Mumpsvirus[RefClinicalmicrobiologyp.273]Mumpsbeginsasaprimaryinfectionintherespiratorytractandspreadsbyviremiatoglandulartissuesincludingthesalivaryglands,pancreas,testesandovaries.
579.Integrationofviralgenomeintohostcell chromosomecanleadsto- a)Malignancy b)Latency c)Alteredgrowth d)Alloftheabove CorrectAnswer-DAns.is'd'i.e.,Alloftheabove[RefClinicalmicrobiologyp.312]Integrationofviralgenomesintohostcellchromosomecancausealterationin: 1. Hostcellsurface2. Metabolicfunction3. Cellgrowthandreplicationpattern4. Malignanttransformation5. Latentinfection
580.Nottrueaboutparamyxoviruses- a)Belongtofamilymyxovirus b)AreDNAviruses c)Havelinearnucleicacid d)Antigenicallystable CorrectAnswer-BAns.is'b'i.e.,AreDNAviruses[RefAnanthanarayan9`h/ep.497-498]MyxovirusesareenvelopedRNAviruses.Theyarecharacterizedbyabilitytoadsorbontomucoprotein(affinityformucin)onerythrocytescausingagglutinationoferythocytes.Majorrouteofinfectionofallthesevirusisrespiratoryroutebydropletinfection.Myxovirusaredividedintotwoimportantfamilies? 1. OrthomyxovirusInfluenza2. ParamyxovirusMumps,measles,RSV,Parainfluenzavirus
581.HTLV-1canbetransmittedby- a)Bloodtransfusion b)Dropletinhalation c)Contaminatedwater d)Animalbite CorrectAnswer-AAns.is'a'i.e.,Bloodtransfusion[RefManualofclinicalmicrobiologyVol.1p.1131]HTLV-1andHTLV-2infectionsaretransmittedby? 1. Sexually(mainlybymalestofemale)2. Vertically(frommothertochildbyprolongedbreastfeeding)3. Parenterally(throughdruguseandbloodtransfusion)
582.Thymusdependentareainspleen- a)Mantellayer b)Perifollicularregion c)Malphigiancorpuscle d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,Malphigiancorpuscle Thymusdependent(T- Thymusindependent(B-cellscollect) cellscollection) 1.Spleen 1.Spleen Periarteriallymphoid Perifollicularregion collect Mantellayer Malphigiancorpusclein 2.Lymphnodewhitepulp Corticalfollicles 2.Lymphnode Germinalcentres Paracorticalarea Medullarycords
583.Precipitationincomparisonto agglutinationrequires- a)LesspH b)Hightemperature c)Specificenzyme d)Solubleantigen CorrectAnswer-DAns.is'd'i.e.,Solubleantigen[RefAnanthanarayan9tVep.105]merav
584.Commonvariabledeficiencyisdueto- a)AbsentBcells b)ReducednumberofBcells c)DefectiveBcelldifferentiation d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,DefectiveBcelldifferentiation[Ref:Robbin's9m/ep.241&8th/ep.233]Mostpatientswithcommonvariableimmunodeficiencyhavenormalornear-normalnumbersofBcellsinthebloodandlymphoidtissues.TheseBcells,however,arenotabletodifferentiateintoplasmacells.Theclinicalmanifestationsarecausedbyantibodydeficiency.Thefeaturecommontoallpatientsishypogammaglobulinemia,generallyaffectingalltheantibodyclassesbutsometimesonlyIgG.
585.CD3isamarkerfor? a)B-cells b)T-cells c)NK-cells d)Monocytes CorrectAnswer-BAns.is'b'i.e.,T-cells[Ref:Robbin's9th/ep.590&8`5/ep.600table(13.5)]CD-3isknownasPanT-cellmarker.
586.InRidealwalkermethod,platesare incubatedfor? a)<2days b)2-3days c)6-8days d)>10days CorrectAnswer-BAns.is'b'i.e.,2-3days[RefTextbookofsterilizatione.7disinfectionp.233]InRidealwalkermethod,forcheckingefficiencyofdisinfectant,bactericidalactivityisdeterminedagainstsalmonellatyphisuspension.Subculturesareperformedfromboththetestandphenolatintervalsof2.5,5,7.5and10minutes.Theplatesareincubatedfor48-72hoursat37?C.
587.ABOnon-secretorsaremoreproneto? a)Infection b)Autoimmunity c)Heartdisease d)Carcinoma CorrectAnswer-A:B:CAns.is'a'i.e.,Infection,'b'i.e.,Autoimmunity&'c'i.e.,Heartdisease[Refwww.dadamo.com]Therearetwotypesofpeople(independentofbloodgroup)Secretor:Thesepersonssecretetheirbloodgroupantigenintootherbodyfluidslikesalivaetc.Nonseretor:Theydonotsecretetheirbloodgroupantigenintobodyfluids.Non-secretorsappeartohaveanincreaseinprevalenceofavarietyofautoimmunediseaselikeankylosingspondylitis,reactivearthritis,GravesdiseaseandSjogren'ssyndrome.Non-secretorsareatagreaterriskofdevelopingdiabetes,MIandheartdisease.Non-secretorsareatagreaterriskforrecurrenturinarytractinfectionsandcandidainfection.Non-secretorshavemoreoraldiseasesandmoredigestiveproblems.
588.Rosewaalertestis- a)Complementfixationtest b)Pricipitationingel c)Ringprecipitation d)Passivehemagglutinationtest CorrectAnswer-DAns.is'd'i.e.,Passivehemogglutinationtest[RefAnanthanarayan8th/ep.107,108,Harrison18th/ep.1469,1470]
589.Preventionofcatheterinducedurinary tractinfectionisby? a)Prophylacticantibiotics b)Useoffacemask c)Closeddrainagetechnique d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,Closeddrainagetechnique[RefMicrobiologyinclinicalpracticep.450]Preventionofcatheter-associatedinfectiondependson: 1. Asepticcathetertechniques.2. Antisepticlubricantcontainingchlorhexidineandlocalinstillationof 1%chlorhexidineintothebladder. 3. Closeddrainagecathatertechnique.4. Excellenthandwashingtechniques,usingchlorhexidinedetergent andgooddryingofhands. 5. Useofglovesandisolationofpatientswithinfectionsduetomultiple antibiotic-resistantstrains.
590.Exampleofprecipitationtestis a)Rosewaalertest b)Widaltest c)Latexagglutination d)Kahntest CorrectAnswer-DAns.is'd'i.e.,KahntestItisaHeterophiletubeagglutinationtest,usedtodiagnoseRickettsiae.
591.Morulaformisseeninwhichinfection? a)Chlamydiae b)Bartonellaquintana c)Mycoplasmahominis d)Ehrlichia CorrectAnswer-DAns.is'd'i.e.,Ehrlichia[RefAnanthanarayanhlep.409;Vasanthakumarip.310]Ehrlichiaegrawwithinphagosomesofphagocytesasmulberry-likeclusterscalledmorula.
592.Whichofthefollowingisnotaninvivo test? a)Elek'sgelprecipitationtest b)Schicktest c)Lepromintest d)Tuberculintest CorrectAnswer-AAns.is'a'i.e.,Elek'sgelprecipitationtest[RefReadbelow]Elek'sgelprecipitationisaninvitrotestfortoxigenicityofCdiphtheriae.Otherthreeoptionsareskintests(i.e.invivotests).
593.PrimoryT-celldeficiencyis- a)Ecto-5'nucleotidasedeficiency b)Commonvariableimmunodeficiency c)DiGeorgesyndrome d)Wiskott-Aldrichsyndrome CorrectAnswer-CAns.is'c'i.e.,DiGeorgesyndrome[Ref:Atlasofimmunologyp.537]I.Cellularimmunodeficiencies(Tcelldefects) 1. Thymichypoplasia(DiGeorgesyndrome)2. Chronicmucocutaneouscandidiasis3. Purinenucleosidephosphorylase(PNP)deficiency II.Combinedimmunodeficiencies(BandTcelldefects) 1. Cellularimmunodeficiencywithabnormalimmunoglobulinsynthesis (Nezelofsyndrome) 2. Ataxiatelangiectasia3. Wiskott-Aldrichsyndrome4. Immunodeficiencywiththymoma5. Immunodeficiencywithshort-limbeddwarfism
594.Monoclonalantibodybindsto? a)Epitope b)Paratope c)Bothepitopeandparatope d)Noneoftheabove CorrectAnswer-AAns.is'a'i.e.,Epitope[Ref:Ananthanarayan9th/ep.88&71*p.81;Harrison18thiep.2673&17th/ep.2036]EpitopeAlsoknownas"antigenicdeterminant".Itisantibodybindingsiteofantigen.
595.Oakley-fulthorpeprocedureis- a)Agglutinationtest b)Precipitationtest c)Singlediffusioninonedimension d)Doublediffusioninonedimension CorrectAnswer-B:DAns.is'd>b'i.e.,Doublediffusioninonedimension>Precipitationtest[Ref:Ananthanarayan9th/ep.105]Immunodiffusiontestsareprecipitationreactioningels.Importantexamplesofimmunodiffusiontestare:- 1. Oudinprocedure->singlediffusioninonedimension.2. Oakleyfulthorpeprocedure-,Doublediffusioninonedimension3. Mancinimethodorradialimmunodiffusion->Singlediffusionintwo dimensions. 4. Ochterlonyprocedure->Doublediffusionintwodimensions
596.Complementdeficiencyhasnotbeen implicatedincausing? a)SLE b)PNH c)Hereditaryangiodema d)Membranousnephritis CorrectAnswer-DAns.is'd'i.e.,Membranousnephritis[RefPariza3'/ep.121]ComplementdeficiencyanddiseaseDeficiencyofearlycomponents(C1,C2,C4)causesimmune-complexdiseases(e.g.SLE),andpyogenicinfections.DeficiencyofC3andC3bcausesrecurrentpyogenicinfections.Terminalcomplementcomponent(C5throughCo)deficienciesanddeficienciesofthealternativepathway(Properdin,C3,FactorD)haveastrongeffectonsusceptibilityto,aswellasseverityof,neisserialinfections.InheriteddeficiencyofC,esteraseinhibitorcasesHereditaryangioneuroticedema.AcquireddeficiencyofDecayaccelaratingfactor(DAF)causesParoxysmalnocturnalhemoglobinuria(PNH).DAFisaregulatorincomplementsystemwhichincreasesdissolutionofC3convertase(C4b2a)
597.MolecularmassofIgG[inKDa] a)150 b)400 c)1000 d)1500 CorrectAnswer-AAns.is'a'i.e.,150 Antibody Molecularmass(KDa)IgG 150 IgA 160,400 IgM 950,1150 IgD 175 IgE 190
598.Latticephenomenonisseenin- a)Neutrilizationreaction b)Complementfixationtest c)Precipitationtest d)Alloftheabove CorrectAnswer-CAns.is'c'i.e.,Precipitationtest[RefTextbookofclinicalmicrobiologyp.785]Thelatticehypothesiswasproposedbymarrack(1934)toexplainthemechanismofprecipitation.Accordingtothisconcept,multivalentantigenscombinewithbivalentantibodiesinvaryingproportiondependingontheantigen-antibodyratiointhereactingmixture.Precipitationresultswhenlargelatticeisformedconsistingofalternatingantigenandantibodymolecules.Thisispossibleonlyinthezoneofequivalence.Inthezoneofantigenorantibodyexcess,thelatticedoesnotenlarge,asthevalenciesoftheantibodyandtheantigen,repectivelyarefullysatisfied.Ineithercasesextensivelatticecannotbeformedandprecipitionisinhibited.Thelatticehypothesisholdsgoodforagglutinationalso.
599.Haptensareimmunogenicwhenthey covalentlybindto- a)Lipidcarrier b)Polysaccharidecarrier c)Proteincarrier d)Anyoftheabovecarrier CorrectAnswer-CAns.is'c'i.e.,Proteincarrier[RefEssentialsofmicrobiologyp.91]HaptenHaptenisasubstance,whichitselfisunabletoinduceantibodysynthesis,i.enon-immunogenicbutmaybeabletoreactspecificallywithantibody.Thus,haptencanfunctionasantigenbutnotasimmunogen.Haptensareincompleteantigens,whichbecomecompleteantigenswhentheycovalentlycombinewithcarriermoleculeorschleper.Aftercombinationwithcarriermolecule,itbecomescompleteantigenandcaninduceanimmuneresponse.
600.IgMappearsinfetusatwhatgestational age- a)10weeks b)20weeks c)30weeks d)atbirth CorrectAnswer-BAns.is'b'i.e.,20weeksIgMistheearliestimmunoglobulinclasstobesynthesizedbythefetus,beginningat20weeksofage.
601.Theserumconcentrationofwhichofthe followinghumanIgGsubclassismaximum? a)IgG1 b)IgG2 c)IgG3 d)IgG4 CorrectAnswer-AAns.is'a'i.e.,IgG1[RefAnanthanarayan9th/ep.97&8`"/ep.98;Harrison19m/ep.372&18tVep.2674]
602.Whichisspecificforacquiredimmunity ? a)Immunologicalmemory b)Affectedbygeneticmakeup c)Noantigenexposure d)Alloftheabove CorrectAnswer-AAns.is'a'i.e.,Immunologicalmemory[RefHarrison19th/ep.372]Acquired(adaptive)immunityisfoundonlyinvertebratesItisbasedonthegenerationofantigenreceptorsonTandBlymphocytesbygermlinegenerearrangements.Itisspecific.Itisdevelopedasaresultofanantigenicstimulus(Immunologicalpriming)orbypassivetransferofantibodies.Itprovidesimmunologicalmemory;subsequentantigenexposureleadstomorerapidandvigorousimmuneresponses.Theadaptiveimmunesystemconsistofduallimbsofcellularandhumoralimmunity.
603.Exampleofneutrilizationreaction- a)VDRL b)Widaltest c)Kahntest d)Naglerreaction CorrectAnswer-DAns.is'd'i.e.,Naglerreaction[RefAnanthanarayan9th/ep.112]ImportantneutralizationtestsareNaglerreaction,dicktestandschicktest.
604.Whichdoesnotstimulateactive immunity- a)Subclinicalinfection b)Clinicalinfection c)Vaccination d)Transplacentalantibodyinnewborn CorrectAnswer-DAns.is'd'i.e.,Transplacentalantibodyinnewborn[RefAnanthanarayan9th/ep.81-83]Adaptive(acquired)immunityisoffollowingtypes:?1)ActiveimmunityItissocalledbecausehost'simmunesystemactivelyproduceimmunity.Antigenicstimulusinducestheimmunesystemtoproduceantibodiesorcellularimmuneresponse.Activeimmunitymaybe:- 1. Natural:Duetoinfection(eitherclinicalorsubclinical/inapparent)2. Artificial:Vaccination(immunization) 2)PassiveimmunityItissocalledbecauseantibodiesareproducedinanotherorganismandthenreceivedpassivelybythehost.Passiveimmunitymaybe:- 1. Natural:Transportofantibodiesacrosstheplacentafrommotherto fetus. 2. Acquired:Administrationofimmunoglobulin/Antibody.
605.Whichofthefollowingisnottrue regardingamoebicliverabscess a)Multipleabscessesismorecommon b)Mayruptureintothepleuralcavity c)Forasymptomaticluminalcarriersdiloxanidefuroateisthedrug ofchoice d)Mostlyinvolvingtherightlobeofliver CorrectAnswer-AAns.is'a'i.e.,MultipleabscessesaremorecommonAmoebicliverabscessisthemostcommonextra-intestinalmanifestationofamoebiasis.ItistheinvolvementoflivertissuebytrophozoitesoftheorganismEntamoebahistolyticaandofitsabscessduetonecrosis.Mostcommonintheposterosuperiorsurfaceoftherightlobe.Usually,thereisonelargesolitaryabscess.-Thenecroticcontentsofliverabscessareclassicallydescribedasanchovy-saucepus.Pleuropulmonaryinvolvementofthemostfrequentcomplicationofamoebicliverabscess.ALAisusuallysolitaryandpyogenicliverabscessisusuallymultiple.MultipleALA,althoughrare,arefrequentlyconfusedwithpyogenicliverabscess.However,Tayaletal.,fromIndiashowedthattheexistenceofmultipleALAisnotuncommonaspreviouslythoughtandsuperinfectionorco-infectionwithpyogenicorganismsiscommoninsuchcases.TreatmentTreatmentdependsonthetypeofinfection:
1)Asymptomaticcarrier-->Luminalagents(Iodoquinol,Paromomycine)-->DiloxanidefuroateistheDOC.2)Acutecolitis(dysentery)-->MetronidazoleorTinidazole+Luminalagent.3)Liverabscess-->MetronidazoleorTinidazoleorOrnidazole+Luminalagent.
606.GeneresponsibleformutationofHBVis ? a)Xgene b)Sgene c)Pgene d)Cgene CorrectAnswer-DAns.is-D-i.e.,CgeneTwocategoriesofnaturallyoccurringHBVvariantshaveattractedthemostattention.OneofthesewasidentifiedinitiallyinMediterraneancountriesamongpatientswithanunusualserologicclinicalprofile.TheyhaveseverechronicHBVinfectionanddetectableHBVDNAbutwithanti-HBeinsteadofHBeAg.ThesepatientswerefoundtobeinfectedwithanHBAmutantthatcontainedanalterationinthepre-coreregionrenderingthevirusincapableofencodingHBeAg.Anothermutation,inthecore-promoterregion,preventstranscriptionofthecodingregionforHBeAgandyieldsanHBeAgnegativephenotype.Patientswithsuchmutationsinthepre-coreregionandwhoareunabletosecreteHBeAgtendtohavesevereliverdiseasethatprogressesmorerapidlytocirrhosis,ortheyareidentifiedclinicallylaterinthecourseofthenaturalhistoryofchronichepatitisBwhenthediseaseismoreadvanced.Both"wild-type"HBVandpre-core-mutantHBVcancoexistinthesamepatient,ormutantHBVmayariselateduringwild-typeHBVinfection
607.Thestatementsregardingfalciparum malariaareallexcept a)Haemoglobinuriaandrenalfailure b)Hypoglycemia c)Cerebralmalaria d)Adequatelypreventedwithchloroquinetherapy CorrectAnswer-DAns.is'd'i.e.,Adequatelypreventedwithchloroquinetherapy[RefCMDT-14Chapter35p.1491]MostspeciesofP.falciparumareresistanttochloroquine(so,itdoesnoteffectivelypreventP.falciparummalaria).Pfalciparummalariacancause:- 1. Cerebralmalariawithimpairedconsciousness.2. Blackwaterfevercausinghemolysis,hemoglobinuriaandrenal failure. 3. Hypoglycemia4. Bleeding5. Pulmonaryedema6. Acidosis
608.Eggsdischargedinurine a)S.mansoni b)S.japonicum c)S.haematobium d)All CorrectAnswer-CAns.is'c'i.e.S.haematobium20mminlengthand0.25mminbreadthfemale.Elongated110-170umlongand40-70umwideeggs,Hasathin,smoothshell,aroundedanteriorendandacharacteristicterminalspinefromthetaperedposteriorendEggdischargedinUrine,InfectiveformisFork-tailedcercariaethatpenetrateskinofhumanswadinginfreshwatercanals.
609.Mostcommonsiteforhydatidcyst a)Lung b)Liver c)Brain d)Kidney CorrectAnswer-BAns.is'b'i.e.,Liver[RefHarrison18thlep.1762]Themajorityofhydatidcystsoccurintheliver,Livercystsoccurmorefrequentlyintherightlobe.
610.Achildcomewithfever,cold,cough, membraneovertonsils;nasalswabistaken,cultureshouldbedoneonwhichmediumforearliestdiagnosis? a)Loffelersserumslop b)L.J.media c)MCConkey'sAgar d)Citratemedia CorrectAnswer-AAns.is'a'i.e.,Loffelersserumslop[Ref:Ananthanarayanelep.233]Fever,cold,coughwithmembraneontonsilssuggestthediagnosisofdiphthesia.ForrapidgrowththespecimenisinoculatedonLoeffer'sserumslop.DiphtheriabacilligrowonLoeffler'sserumslopeveryrapidlyandcoloniescanbeseenin6-8hours,longbeforeotherbacteriagrow
611.Whatisp24? a)EnvelopantigeninHIV b)CoreantigeninHIV c)GenomeofHIV d)Shellantigen CorrectAnswer-BAns.is'b'i.e.,CoreantigeninHIV[RefAnanthanarayan8thiep.571]A.EnvelopantigensSpikeantigen-gp120(Principalenvelopeantigen)Transmembranepedicleprotein-gp41B.ShellantigenNucleocapsidprotein-p18C.CoreantigensPrincipalcoreantigen-p24Othercoreantigens-p15,p55Polymeraseantigens-p31,p51,p66
612.Invasiveinfectionscausedbyallexcept ? a)Shigella b)Salmonella c)V.cholerae d)Yersinia CorrectAnswer-CAns.is'c'i.e.,V.cholerae[RefHarrisontelep.1084]
613.AchildwithfeverwithABCs&pusin stools,causativeorganismis? a)ETEC b)EHEC c)EPEC d)EAEC CorrectAnswer-BAns.is'b'i.e.,EHEC[RefHarrison18thlep.1084]FeverwithRBCandpusinstoolssuggestinflammatorydiarrhea.AmongstthegivenoptionsEHECcausesinvasion.
614.Painlessgenitalulcerinmalewith evertedmarginisseenin? a)Syphilis b)Chancroid c)Herpes d)LGV CorrectAnswer-AAns.is'a'i.e.,Syphilis[RefHarrison18th/ep.1382,Jawetz22"/ep.642]Painlessinduratedulcerwithevertedmargins,h/oofsexualexposureandlackofsystemicsymptomsfavoursthediagnosisofsyphilis.
615. Whichorganismcanbeisolatedfrom stool&sputum- a)Paragnomus b)Fasciola c)Chlornchis d)P.carini CorrectAnswer-AAns.is'a'i.e.,Paragnomus[RefRajeshkaryakartep.212]Twoorganismcanbeisolatedfrombothsputumandstool:- 1. TrophozoiteofE.histolytica2. EggsofParagonimus
616.Largestintestinalprotozoais? a)E.coli b)Balantidiumcoli c)Giardia d)T.gondii CorrectAnswer-BAns.is'b'i.e.,Balantidiumcoli[RefPanikerp.111] Largestprotozoa Balantidumcoli Smallestintestinalamoeba DientamoebafragilisSmallesttapewormfoundin H.nana humanintestineLargesthelminth(largest T.saginata(beeftapeworm) worm)Largestliverfluke F.hepaticaLargesttrematodeinfectingman FasciolopsisbuskiLargestNematode Ascaris SmallestNematode- Trichinella Onlyprotozoanparasitefoundin Giardialamblia smallintestineofmanOnlyciliateprotozoanparasiteof Balantidumcoli man-Parthenogenicworm(femaleis Strongyloidesstercoralis. abletoproducefertileeggsorlarvaewithoutfertilization)
617.Rhaditiformlarvaeisseenin? a)Teniasolium b)Strongyloides c)D.latum d)Trichenella CorrectAnswer-BAns.is`b'i.e.,Strongyloides[RefPanikar6th/ep.171]Rhabditiformlarvaisthefirststagefeedinglarvafoundinsomenematodes.Itisnon-infective.Filiformlarvaisthenonfeedinginfectivelarvainsomenematodes.Rhabditiformlarvaandfiliformlarvaarefoundinfollowingimportantnematodes
618.Burkholderiacepaciaisresistantto whichofthefollowingdrugs: a)Ceftazidime b)Trimethoprim-sulfamethoxazole c)Temocillin d)Cefotetan CorrectAnswer-DAnswer:D.CefotetanB.cepaciacomplexstrainsareintrinsicallyresistanttoawiderangeofantimicrobialagents,includingaminoglycosides,polymyxin,firstandsecondgenerationcephalosporins,andcarboxypenicillinsAntimicrobialagentsthatareeffectiveagainstB.cepaciacomplexincludemeropenem,ceftazidime,piperacillin,temocillin,andtrimethoprim-sulfamethoxazole.
619.ShinglesIscausedbywhichofthe following? a)Varicella-zoster b)Herpessimplex c)CMV d)None CorrectAnswer-AAns.A.Varicella-zosterShingles,alsocalledherpeszoster,isapainfulskinrash.Shinglesiscausedbyreactivationofthevaricellazostervirus,thesamevirusthatcauseschickenpox.
620.Ureabreathtestisusedfordiagnosisof: a)H.pylori b)Campylobacterjejuni c)E.coli d)Lactobacillus CorrectAnswer-AAnswer:A.H.pyloriTheureabreathtestisarapiddiagnosticprocedureusedtoidentifyinfectionsbyHelicobacterpylori,aspiralbacteriumimplicatedingastritis,gastriculcer,andpepticulcerdisease.ItisbasedupontheabilityofH.pyloritoconvertureatoammoniaandcarbondioxide
621.Hyperacutegraftrejectionoccursafter howmuchtime? a)24hours b)2weeksright c)Inminutes d)Years CorrectAnswer-CAnswer:C.InminutesHyperacuteTransplantRejectionoccursalmostimmediatelyandisoftenevidentwhileyouarestillinsurgery.ItiscausedbyaccidentalABOBloodtypemismatchingofthedonorandrecipientwhichalmostneverhappensanymore..Acuteonsetisinfewweekstomonth.Chroniconsetisfrommonthstoyears.
622.Australianantigenforhepatitisbis? a)HbSag b)HbEag c)HbDag d)HbVDna CorrectAnswer-AAnswer:A.HbSagHBsAg(alsoknownastheAustraliaantigen)isthesurfaceantigenofthehepatitisBvirus(HBV).ItindicatescurrenthepatitisBinfection.
623.Whichfungusismostcommonly associatedwithorbitalcellulitisinpatientswithdiabeticketoacidosis. a)Candida b)Mucor c)Aspergillus d)Rhizopus CorrectAnswer-CAnswer:C.AspergillusOrbitalcellulitistermisreservedforinfectionsbehindtheorbitalseptumwhichmayormaynotspillovertolids.BacterialOCismorecommoninchildrenandfulminantinfection(&ischemicinfarction)withMucororAspergillustypicallyaffectspatientswithdiabetes(espketoacidosis)andimmunosuppression.PresentationisExtensiveswellingoflidswithchemosisoftenobscureproptosis(i.e.mostcommonlylateral&downwards).ProptosiswithimpairedmobilityresultingindiplopiaPainissevere,increasedbymovementofeyeorpressureUnilateral,tender,warm&redperiorbitaledema,painfulophthalmoplegia.
624.SabinFeldmandyetestisusedfor diagnosisofwhichofthefollowingcondition: a)Botulism b)Toxoplasmosis c)Sarcoidosis d)Yellowfever CorrectAnswer-BAnswer:B.ToxoplasmosisASabin?Feldmandyetestisaserologictesttodiagnosefortoxoplasmosis
625.AcuteHemorrhagicConjunctivitisis causedbywhichofenterovirustype? a)69 b)68 c)70 d)71 CorrectAnswer-CAnswer:C.70Acutehemorrhagicconjunctivitis(AHC)ischaracterizedbyconjunctivalcongestion,vasculardilatation,andonsetofedema.SerologicstudieshavebeenusefulinshowingthepresenceofneutralizingantibodiestoCoxsackiegroupA24(CA24)andenterovirusE70(EV70)strainsasthecausativeagent.
626.Echinococcusgranulosusarecommonly seeninwhichofthegivenanimals: a)Dog b)Cat c)Fox d)Pig CorrectAnswer-AAnswer:A.DogEchinococcusgranulosus,alsocalledthehydatidworm,hypertape-wormordogtapeworm.Domesticdogs(Canisfamiliaris)havebeenrecognisedasthedefinitivehostoftheparasite.
627.Ananaerobecausingmultipleabscess withdischargingsinuses,demonstratingsulphurgranulesinpusis? a)Actinomycetes b)Nocardia c)Salmonella d)Tularemia CorrectAnswer-AAnswer:A.ActinomycetesActinomycosisisararesubacutetochronicinfectioncausedbythegram-positivefilamentousnon-acidfastanaerobictomicroaerophilicbacteria,Actinomyces.Thechronicformhasmultipleabscessesthatformsinustractsandareassociatedwithsulfurgranules.About70%ofinfectionsareduetoeitherActinomycesisraeliiorActinomycesgerencseriae.Thecharacteristicofthediseaseisthesulfurgranuleswhichareyellow.Theyareformedprimarilybymycelialfragmentswithsomeproteinaceouspolysaccharidecomplexes,whichactasaresistancemechanismtoavoidandinhibitphagocytosis.Multipleabscesswithdischargingsinuses,demonstratingsulphurgranulesinpusarecharacteristicsofactinomycetes
628.Wholebloodisusedasasamplefor whichtest? a)Bacteria b)IGRA c)Genexpert d)Virus CorrectAnswer-BAnswer:B.IGRAInterferon-GammaReleaseAssays(IGRAs)arewhole-bloodteststhatcanaidindiagnosingMycobacteriumtuberculosisinfection
629.Whichorganismcausingacutebacterial prostatitis? a)Enterococcus b)Streptococcusviridans c)Peptostreptococcus d)E.coli CorrectAnswer-DAnswer:D.E.coliAerobicgram-negativebacilliarethepredominantpathogensinbacterialprostatitis.E.colicause50%?80%ofcases;otherpathogensincludeEnterobacteriaceae(eg,KlebsiellaandProteus,whichaccountfor10%?30%ofcases),Enterococcusspecies(5%?10%)
630.Whichofthefollowingorganism releaseshistamineandcausescombroidfishpoisoning- a)Salmonella b)Staphylococcus c)P.aeruginosa d)Weissella CorrectAnswer-CAnswer:C.P.aeruginosaScombroidpoisoningisoneofthemostcommoncausesofmorbidityassociatedwithfishintakewhichhavenotbeenrefrigeratedproperlyfromthetimetheywerecaughtuntilthetimetheywereserved.Bacteriaactoncompoundsinthefish,releasinghistamine.Processisinducedbyenzymesproducedbyprimarilyentericgram-negativebacteria(e.g.,Morganellamorganii,Escherichiacoli,KlebsiellaspeciesandPseudomonasaeruginosa)foundinthefish'scutisandintestines.,.
631.Whoisthefatherofmicrobiology? a)A.V.L.hook b)Robertbrown c)J.CBose d)Pasteur CorrectAnswer-AAnswer:A.A.V.L.hook"AntonivanLeeuwenhoek"iscommonlyknownas"theFatherofMicrobiology.AntoniePhilipsvanLeeuwenhoek(24thOct,1632?26thAug,1723)isknownas'TheFatherofMicrobiology'.Hewasknownsobecauseofhiscontributionstowardstheestablishmentofmicrobiology.HewasscientistfromDelft,Netherlandsandisconsideredtobe'TheFirstMicrobiologistintheWorld'.leeuwenhoekiscalledasfatherofmicrobiology.Hewasthefirstpersontoseebacteriathroughhisselfmadesinglelensedmicroscope.Andhenamedthem"animalcules".LouisPasteurisknowas"fatherofmordenmicrobiology".
632.Cutaneouslarvamigranscausedby whichorganism? a)Strongyloides b)Toxocaracanis c)Ancylostomabraziliense d)Necatoramericanus CorrectAnswer-CAnswer:C.AncylostomabrazilienseCutaneouslarvamigrans(CLM)/Itisaskindiseaseinhumans,causedbythelarvaeofvariousnematodeparasitesofthehookwormfamily(Ancylostomatidae).ThemostcommonspeciescausingthisdiseaseintheAmericasisAncylostomabraziliense.Theseparasitesliveintheintestinesofdogs,catsandwildanimalsandshouldnotbeconfusedwithothermembersofthehookwormfamilyforwhichhumansaredefinitivehosts,namelyAncylostomaduodenaleandNecatoramericanus.Colloquiallycalledcreepingeruptionduetoitspresentation,thediseaseisalsosomewhatambiguouslyknownas"grounditch"or(insomepartsoftheSouthernUSA)"sandworms",asthelarvaeliketoliveinsandysoil.Anothervernacularnameisplumber'sitch.ThemedicaltermCLMliterallymeans"wanderinglarvaeintheskin"
633.Afterkidneytransplantationwhich organismsinfectionismorelikelytohappens- a)CMV b)Klebsiella c)Streptococcus d)Staphylococcus CorrectAnswer-AAnswer:A.CMVCMVisthemostcommonviralinfectionafterKidneyTransplantation.MostcommonCMVsyndromeinkidneytransplantpatientisfever(mostcommon),leukopenia,hepatosplenomegaly,myalgiaandarthralgia.
634.Vectorforzikavirusis- a)Aedes b)Culex c)Anopheles d)Noneofthese CorrectAnswer-AAns:A.AedesZikavirusdiseaseiscausedbytheZikavirus,whichisspreadtopeopleprimarilythroughthebiteofaninfectedmosquito(AedesaegyptiandAedesalbopictus).Theviruscanalsobetransmittedthroughsex.Thesearethesamemosquitoesthatspreaddengueandchikungunyaviruses.Amosquitogetsinfectedwithaviruswhenitbitesaninfectedpersonduringtheperiodoftimewhentheviruscanbefoundintheperson'sblood,typicallyonlythroughthefirstweekofinfection.MedicalMicrobiologyandImmunology14/e-pg;395
635.Allofthefollowingis/arehaving superantigenPropertyExcept a)Vibriocholera b)Streptococcalpyrogenic c)Staphylococcalenterotoxins d)Noneofthese CorrectAnswer-AAnswer-A-VibrioCholeraSAgsareproducedbysomepathogenicvirusesandbacteriamostlikelyasadefensemechanismagainsttheimmunesystem.Toxicshocksyndrometoxin(TSST-1),epidermolytictoxinandotherstaphylococcalenterotoxinaresuperantigens.ThesesuperantigenscanbindMHCmoleculesoutsidethepeptide-bindingcleft.Consequently,superantigencanactivateupto10%ofT-cellsinanonspecificmannerwhichinturnleadstothereleaseoflargequantitiesofcytokines.Jawetz27/e-pg-135
636.TypeAbioterrorismAgent- a)Chikungunya b)Anthrax c)Hendra d)Influenza CorrectAnswer-BAnswer-B-AnthraxCategoryAagents-consistsoftheagentsthatareconsideredthehighestriskIncludedamongCategoryBagentsisonethatcouldconceivablythreatenwaterandfoodsafety.CategoryCincludespathogensthatareconsideredemerginginfectiousdiseasethreatsandwhichcouldbeengineeredformassdissemination. CategoryA CategoryB CategoryC Anthrax Caliciviruses AntimicrobialResistance Botulism Chikungunya Hendra Dengue Cholera Influenza(highlypathogenicstrains) Ebola E.coliO157:H7 MERS Hantavirus HepatitisA Nipah Lassa Ricintoxin Prions Marburg Salmonella Rabies Plague Typhusfever SARS Smallpox Yellowfever Tick-Borneencephalitis Tularemia Zika Tuberculosis Jawetz27/e-pg-417
637.CulturemediausedforE.coli0157:H7is a)SMAC b)WilsonandBlairmedium c)PotassiumtelluriteinMcleod'smedium d)Deoxycholatecitrateagar(DCA) CorrectAnswer-AAnswer-A-SMACAnenterohemorrhagicbacterialstrain,E.coliO157:H7infectsthealimentarytractandinducesabdominalcrampswithhemorrhagicdiarrhea.TransmissionofE.coliO157:H7occursviathefecal-oralrouteafterconsumptionofcontaminated,undercookedliquidsandfoods.MacConkey-SorbitolChromoSelectAgar(SMAC)isrecommendedforselectiveisolationofEscherichiacoli0157:H7fromfoodandanimalfeedingstuffs.MacConkeySorbitolAgarisbasedontheformulationdescribedbyRappaportandHenigh.ThemediumcontainssorbitolinsteadoflactoseanditisrecommendedforthedetectionofenteropathogenicstrainsofE.coli0157:H7whichfermentslactosebutdoesnotfermentsorbitolandhenceproducecolorlesscolonies.SorbitolfermentingstrainsofE.coliproducepink-redcolonies.Theredcolorisduetotheproductionofacidfromsorbitol,absorptionofneutralredandasubsequentcolourchangeofthedyewhenthepHofthemediumfallsbelow6.8.https://www.sigmaaldrich.com/analytical-chromatography/microbiology/microbiology-products.html?TablePage=18297647
638.DonovanosisisCausedBy- a)H.ducreyi b)Leishmaniadonovani c)K.granulomatis d)Treponemapallidum CorrectAnswer-CAnswer-C-K.GranulomatisDonovanosisisasexuallytransmittedgenitalulcerdisease.Thebacteriumthatcausesdonovanosis(Klebsiellagranulomatis)infectstheskinaroundthegenitals,groinoranalareaandcausesulcersanddestructionoftheskin.
639.FungalInfectionwhichisacquiredby traumaticinoculationis? a)Sporothrix b)Blastomycosis c)Coccidioides d)Paracoccidioides CorrectAnswer-AAnswer-A-SporothrixSporothrixschenckiiisathermallydimorphicfungusthatlivesonvegetation.Itisassociatedwithavarietyofplants,grasses,trees,sphagnummoss,rosebushes,andotherhorticulturalplants.TheconidiaorhyphalfragmentsofS.schenckiiareintroducedintotheskinbytrauma.Followingatraumaticintroductionintotheskin,S.schenckiicausessporotrichosis,achronicgranulomatousinfection.Thismanifestationmimicschroniccavitarytuberculosisandtendstooccurinpatientswithimpairedcell-mediatedimmunity.Jawetz27/e-pg-670
640.Whichofthefollowingisnotinvolvedin urethritis a)Trichomonas b)H.ducreyi c)Chlamydia d)Gonococcus CorrectAnswer-BAnswer-B-H.ducreyiBacteriathatcommonlycauseurethritistoinclude:E.coliandotherbacteriapresentinthestoolGonococcus,whichissexuallytransmittedandcausesgonorrhea.Chlamydiatrachomatis,whichissexuallytransmittedandcauseschlamydia.Theherpessimplexvirus(HSV-1andHSV-2)canalsocauseurethritis.Trichomonasisanothercauseofurethritis-https://www.webmd.com/a-to-z-guides/urethritis-symptoms-causes-treatments#1;Jawetz27/e-pg-746
641.Apatientcomplainsaboutnausea, vomitingandstomachcrampsafterattendingasocialgatheringparty,whichcausativeorganismislikelyresponsibleforFoodPoisoningwithin3hours. a)Staphylococcusaureus b)Salmonella c)Clostridiumbotulinum d)Clostridiumperfringens CorrectAnswer-AAnswer-A-StaphylococcusaureusStaphfoodpoisoningischaracterizedbyasuddenstartofnausea,vomiting,andstomachcramps.Mostpeoplealsohavediarrhea.Symptomsusuallydevelopwithin30minutesto6hoursaftereatingordrinkinganitemcontainingStaphtoxinandlastnolongerthan1day.Severeillnessisrare.Theillnesscannotbepassedfromonepersontoanother.https://www.cdc.gov/foodsafety/diseases/staphylococcal.html
642.A46-year-oldwomanwithHIVcomplains severepersistentdiarrhea,HistologicalInvestigationwasperformed,IdentifytheorganismcausingdiarrheainHIVPatient. a)Cryptosporidium b)Staphylococcusaureus c)Salmonella d)Clostridiumbotulinum CorrectAnswer-AAnswer-A-Cryptosporidium*TheoriginofinfectiousdiarrheainpatientswithAIDScanbedividedinto2generalcategories:thatcausedbycommonpathogensandthatcausedbyopportunisticpathogens.*ThemostcommoninfectiousorganismscausingAIDS-relateddiarrheainclude-Cytomegalovirus(CMV)-TheparasitesCryptosporidium,-Microsporidia-Giardialamblia*AndthebacteriumMycobacteriumavium-intracellulare(MAC).*Otherbacteriaandparasitesthatcausediarrhealsymptomsinotherwisehealthypeoplemaycausemoresevere,prolongedorrecurrentdiarrheainpeoplewithHIVorAIDShttps://aidsinfo.nih.gov/news/175/aids-related-diarrhea
643.OrganismCausingLGV a)Chlamydiatrachomatis b)Neisseriagonorrhoeae c)Treponemapallidum d)Haemophilusducreyi CorrectAnswer-AAnswer-A-ChlamydiatrachomatisLymphogranulomavenereum(LGV)isalong-term(chronic)infectionofthelymphaticsystem.Itiscausedbyanyofthe3differenttypes(serovars)ofthebacteriaChlamydiatrachomatis.Thebacteriaarespreadbysexualcontact.Theinfectionisnotcausedbythesamebacteriathatcausegenitalchlamydia.Chlamydiatrachomatiscauseseye(conjunctivitis,trachoma),respiratory(pneumonia),andgenitaltract(urethritis,lymphogranulomavenereum)infections.DiagnosismadewiththenucleicacidtestforC.trachomatis,LGVserovarsdiagnosedserologically.LangeReviewofMedicalMicrobiology&Immunology14/e208
644.Whichinterleukinresponsiblefor producingIgEfromBcells a)IL1 b)IL3 c)IL4 d)BothB&C CorrectAnswer-CAnswer-C,IL4IgEisproducedbyplasmacellslocatedinlymphnodesdrainingthesiteofantigenentryorlocally,atthesitesofallergicreactions,byplasmacellsderivedfromgerminalcentersdevelopingwithintheinflamedtissue.IgEantibodyproductionrequiresTH2cellsthatproduceinterleukin-4(IL-4)andIL-13anditcanbeinhibitedbyTH1cellsthatproduceinterferon-(IFN-).https://www.ncbi.nlm.nih.gov/books/NBK27117/
645.HbsAgisbasedonwhichprinciple a)Immunochromatographyassays b)Chemiluminescence c)ELISA d)Immunofluorescence CorrectAnswer-AAnswer-A-ImmunochromatographyassaysHBVchroniccarriersarethoseinwhomHBsAgpersistsformorethan6monthsinthepresenceofHBeAgoranti-HBe.HBsAgmaypersistforyearsafterthelossofHBeAg.Themostusefuldetectionmethodsareenzyme-linkedImmunosorbentassayforHBVantigensandantibodiesandPCRforviralDNA-Jawetz27/epg-504Serologicalassaysdetectthehostimmuneresponse(antibodiestoHCV)oraviralantigen(HBsAg,HCVcAg).Theyarebasedontheimmunoassayprincipleandareavailableintheformofrapiddiagnostictests(RDTs)orlaboratory-basedenzymeimmunoassays(EIAs),chemiluminescenceimmunoassays(CLIAs)andelectrochemiluminescenceimmunoassays(ECLs).-https://www.ncbi.nlm.nih.gov/books/NBK442281/
646.NosocomialInfectionoccurswithin? a)A-48 b)B.72 c)C.24 d)D.50 CorrectAnswer-AAnswer-A-48hoursAhospital-acquiredinfection(HAI),alsoknownasanosocomialinfection,isaninfectionthatisacquiredinahospitalorotherhealthcarefacility.Nosocomialinfectionscanbedefinedasthoseoccurringwithin48hoursofhospitaladmissionorwithin3daysofdischargeor30daysofoperation.Somewellknownnosocomialinfectionsinclude:ventilator-associatedpneumonia,Methicillin-resistantStaphylococcusaureus,Candidaalbicans,Acinetobacterbaumannii,Clostridiumdifficile,Tuberculosis,Urinarytractinfection,Vancomycin-resistantEnterococcus,andLegionnaires'disease.https://www.ncbi.nlm.nih.gov/books/NBK441857/
647.Whichofthefollowingcellcomponents producedbyNeisseriagonorrhoeaeisresponsibleforattachmenttohostcells? a)Lipooligosaccharide b)Pili(fimbriae) c)IgA1protease d)Outermembraneporinprotein CorrectAnswer-BAnswer-B-Pili(fimbriae)Piliarehair-likeappendagesthatextenduptoseveralmicrometersfromthegonococcalsurface.Theyenhanceattachmenttohostcellsandresistancetophagocytosis.Theyaremadeupofstackedpilinproteins.Theaminoterminalofthepilinmolecule,whichcontainsahighpercentageofhydrophobicaminoacids,isconserved.Theaminoacidsequencenearthemidportionofthemoleculealsoisconserved;thisportionofthemoleculeservesinanattachmenttohostcellsandislessprominentintheimmuneresponse.Theaminoacidsequencenearthecarboxyl-terminalishighlyvariable;thisportionofthemoleculeismostprominentintheimmuneresponse.ThepilinsofalmostallstrainsofN.gonorrheaareantigenicallydifferent,andasinglestraincanmakemanyantigenicallydistinctformsofpilinJawetz27/e-pg-282
This post was last modified on 23 November 2021