Download PGIMER (Post Graduate Institute of Medical Education & Research, Chandigarh) 2020 May Physio Solved Question Paper
except:
a)SodiumabsorptionoccursinDCT
b)Potassiumisbothsecretedandabsorbedintubules
c)GlucoseisreabsorbedinDCT
d)All
e)None
CorrectAnswer-C
Ans.Ci.e.GlucoseisreabsorbedinDCT
RENALHANDLINGOFSUBSTANCE
InPCT:
60-70%offilteredwaterreabsorbedpassively.
Coupledmainlytosodiumreabsorption.
Glucose&aminoacidsAbsorbedcompletely(100%).
Maximum(90%)bicarbonateabsorption.
InDCT:
Principal(P)cellsreabsorbsodium&waterfromlumen
&secretepotassiumintolumen.
Intercalated(I)cellsreabsorbpotassium&secrete
hydrogenintolumen.
Sodiumreabsorptionapproximately7%filteredNa2+reabsorbed.
InHenleloop:
Thindescendingsegment-
Waterreabsorption:Highlypermeabletowater.
Reabsorptionofsolutes:Impermeabletosolutes(Na2+,Cl-&
urea).
Minimalureasecreted.
Inthinascendinglimb:
NaCl-reabsorptionoccurs-DuetohighNaCl-permeability.
Lesspermeabletowater.
Thickascendinglimb:
Sodium,Potassium&Chloridereabsorption:
TransportsoneNa2+,oneK+,&twoCl-.
Activesodiumabsorptionoccurs.
30%filteredNa2+reabsorbed.
Waterreabsorption:Totallyimpermeabletowater.
2.Bloodbrainbarrierisabsentin?
a)Adenohypophysis
b)Neurohypophysis
c)Hypothalamus
d)Thalamus
e)None
CorrectAnswer-B
Ans.is'b'i.e.,Neurohypophysis
Bloodbrainbarriersexistbothatthechoroidplexusandatthetissue
capillarymembranesinessentiallyallareasofthebrainparenchyma
exceptinsomeareosofthehypothalamus,pinealgland,adarca
posttema,wheresubstancesdiffusewithgreatereaseintothetissue
spaces.
FourareasthatareoutsideofBBBare(l)theposteriorpituitary
(neurohypophysis)andtheadjacentventralpartofthemedian
eminenceofthehypothalamus,(2)theareapostrema,(3)the
organumvasculosumofthelaminaterminalis(OVLT,supraoptic
crest),and(4)thesubfornicalorgan(SFO).
Referredtocollectivelyasthecircumventricularorgans
3.TrueregardingHbA2is/are?
a)Ithasmorecapacitytocarryoxygen
b)ConcentrationismorethanHbA
c)LevelisincreasedinThalasemia
d)Consistsof2alphaand2betachains
e)Noneoftheabove
CorrectAnswer-B
Ans.is'c'i.e.,LevelisincreasedinThalassemia
Ref:Ganong23d/ep.523-525https://www.aafp.org/alp/2009/08
15/p339.html
"Thehemoglobinelectrophoresiswithbetathalassemiatraitusually
hasreducedorabsentHbA,elevatedlevelsofHbA2.andincreased
HbF.
However,anormalconcentrationofHbA2doesnotruleoutbeta
thalassemiatrait.especiallyiftherewascoexistentirondeficiency,
whichcanlowerHbA2levelsintothenormalrange."
"HemoglobinA2maybeincreasedinbetathalassemiaorinpeople
whoareheterozygousforthebetathalassemiagene.
4.TRUEstatement(s)regarding"loopof
Henley"inkidneyis/are?
a)AscendinglimbactivelyabsorbsNa
b)AscendinglimbactivelyabsorbsCl
c)Ascendinglimbsecreteswaterinlumen
d)Descendinglimbsecreteswater
e)DescendinglimbreceiveshyperosmolarfluidfromPCT
CorrectAnswer-A:B
Ans.is'a'i.e.,AscendinglimbactivelyabsorbsNa+&'b'i.e.
AscendinglimbactivelyabsorbsCl-
Ref:Ganong25th/eP.680-691;Essentialsofmedicalphysiologyp.
271
LOOPOFHENLE
TheloopofHenlehasathindescending,athinascendinganda
thickascendingsegments.
REABSORPTIONINTHINASCENDINGLIMB:
NaCl-reabsorptionoccurs-
DuetohighNaCl-permeability.
Lesspermeabletowater.
Tubularfluidisiso-osmotic.
REABSORPTIONINTHICKASCENDINGLIMB:
Sodium,Potassium&Chloridereabsorption:
By"Secondaryactivetransport"-
ThroughNa2+-K+-2Cl--carriertransporter.
TransportsoneNa2+,oneK+,&twoCl-.
Activesodiumabsorptionoccurs.
30%filteredNa2+reabsorbed.
Waterreabsorption:
Totallyimpermeabletowater.
Ascendingsegmentalsoreferred"Diluting"segment:
Duetosodium&soluteabsorptionwithoutwater.
Resultingintubularfluiddilution.
Tubularfluidishypotonic.
5.Iodineistransportedtothethyroidgland
by?
a)Activetransport
b)Diffusion
c)Passivetransport
d)Pinocytosis
e)None
CorrectAnswer-A
Ans.is'a'i.e.,Activetransport[Ref:Ganongjs24th/ep.3411]
Iodineuptakeforthyroidhormonesynthesis:
Iodineuptakemediatedbythyroidfollicularcellsfromtheblood
plasmaisthefirststepforthesynthesisofthyroidhormones.
Thisingestediodineisboundtoserumproteins,especiallyto
albumins.
Therestoftheiodinewhichremainsunlinkedandfreein
bloodstream,isremovedfromthebodythroughurine.
Basolateralmembraneofthyroidcells(follicularcells)haveactive
transportsystemforiodineuptake-Na+:I-symporter(NlS)
(Secondaryactivetransport).
ThistrappingstimulatedbyTSH,
6.Antioxidanteffectsareshownby?
a)VitaminC
b)VitaminE
c)Selenium
d)Zinc
e)VitaminB
CorrectAnswer-A:B:C:D
Ans.is'a'i.e.,VitaminC,'b'i.e.VitaminE,'c'i.e.,Selenium&'d',
Zinc
RefHarper's30th/ep.565;Robbins'sth/ep.66-67,http://
www.rroij.coml
Naturallyoccurringantioxidants:
Alkaloidsandrelatedcompounds
Aminoacidsandpeptidederivatives:-cysteine,tryptophan,
melatonin,andtryptamine
Vitamins:-Betacarotene,VitaminA,VitaminC,VitaminE
(tocopherol)
Minerals:-selenium,zinc
Enzymes:-catalase,superoxidedismutase(SOD),andglutathione
peroxidase
Flavonoids&Isoflavonoids:Chalconesandcatechins
Carnosine
Clorogenic&melanicacids
Curcuminandderivatives
Ergothioneine
Freephenolicacids
Hydroquinonesandquinones
Lignans
Lipoicacid
Lycopene
Tetrapyrroles
Uricacidandotherourines
7.Rightcombinationofsensoryreceptorand
sensationcarriedbythemincludes?
a)Krouse'sbulb-pressure
b)Paciniancorpuscels-vibration
c)Meissner'scorpuscles-pressure
d)Ruffini'sendorgans-pressure
e)Merkel'sdisc-coldtemperature
CorrectAnswer-B:D
Ans.is'b'i.e.,Paciniancorpuscles-vibration&'d'i.e.Ruffini's
endorganspressure
[Ref:Guyton12th/ep.560tableG6.1);Principlesofmedical
physiologyp.647,648
Tactile(Touch)receptor:
Whetheratactilereceptorsensespressureorvibrationdependson
whetherreceptorisfastlyadaptingorslowlyadapting.
Touch,pressure,&vibrationaredifferentformsofsamesensation.
Pressureisfeltwhenforceappliedonskinissufficienttoreachdeep
receptors.
Touchisfeltwhenforceisinsufficienttoreachdeepreceptors.
Hence,detectedbysuperficialreceptors(Merkel'sdisc&Meissner's
corpuscle).
Vibrationsarerhythmicvariationsinpressure.
I.e.Rhymicvariationsofforcethatreachesdeepreceptors.
Divisions:
2a.Slowlyadapting:
Examplesinclude,"Oneeachfromsuperficial&deepcutaneous
receptors"
Ruffini'sendorgan-
Meanttodetectsustainedpressure.
Uselessforvibrations.
Merkel'sdisk-
Detecttwo-pointdiscrimination.
2b.Rapidlyadapting:
Examples,
"Oneeachfromsuperficial&deepcutaneousreceptors"
Paciniancorpuscle-
Stopsdischargeinresponsetosustainedpressure.
Usefultodetectvibrations-I.e.,whenpressurefluctuatesrapidly.
Meissner'scorpuscle-
Detectsurfacetexture.
Hence,HighertherateofreceptoradaptationGreateris
detectablevibrationfrequency.
3.Basedontypeoftactilesensationsdetected:
3a.Superficialsensations:
Generallytouch
ByMeissner'scorpuscle(detectsurfacetexturei.e.roughor
smooth)
ByMerkel'sdisc(detecttwo-pointdiscrimination).
3b.Deepsensations:
Pressure(Deeptouch)-DetectedbyRufiniorgan.
Vibrations-DetectedbyPaciniancorpuscle.
SUMMARY:
1.Superficialcutaneousreceptors:
Detecttouch(Superficialsensation)
Merkel'sdisk-Slowlyadapting&detecttwo-point
discrimination.
Meissner'scorpuscle-Rapidlyadapting&detectsurface
texture.
2.Deepcutaneousreceptors:
Detectdeeptouch,pressure,&Vibration.
Ruffini'sendorgan-Slowlyadapting&detectsustained
pressure/deeptouch.
Paciniancorpuscle-Rapidlyadapting&detect
vibrations(usefulonlywhenpressurefluctuatesrapidly.i.e.during
vibrations).
Highertherateofadaptationofreceptor,thegreatervibration
frequencyitcandetect.
8.TRUEregardinghypoxemiais/are?
a)Decreaseinventilation
b)Decreaseindeliveryofoxygentotissues
c)Inadequateutilizationofoxygenbytissuesdespitenormal
deliveryofoxygen
d)Decreasedoxygenpressureinblood
e)Alloftheabove
CorrectAnswer-A:D
Ansis'a'i.e.,Decreaseinventilation&'d'i.e.Decreasedoxygen
pressureinblood.
[Ref:Ganong25th/ep.647624/ep.649;Principlesofmedical
physiologyp.354,355;
https://www.ncbi.nlm.nih.gov/pmc/articles/PMc52341994]
Optionb&carerelatedwithhypoxia,nothypoxemia.
Hypoxemiaandhypoxia:
Thetermhypoxiaandhypoxemiaarenotsynonymous.
Hypoxemiaisdefinedasadecreaseinthepartialpressureof
oxygeninthebloodwhereashypoxiaisdefinedb!reducedlevelof
tissueoxygenation.
Hypoxiacanbeduetoeitherdefectivedeliveryordefective
utilizationofoxygenbythetissues.
Causesofhypoxemia
Theinspiredairhasreducedoxygencontent(e.g.,athighaltitudeor
duetoothercauses).
Insufficientgasexchangeiscausedbyalveolarhypoventilation.
9.AccordingtoWHO,normalsemenfindings
are?
a)Volume-1.5ml
b)Concentration-15million/ml
c)Progressivemotility->40%
d)Normalmorphology->10%
e)Ph-<6.3
CorrectAnswer-A:B
Ans.is'a'i.e.,Volume-1.5ml&'b'i.e.Concentration-15
million/mlhttps://www.institutobernabeu.com/foro/en/2014/02/17/semen-
quality-parameters-according-to-the-world-health-organisation-who/
TheWorldHealthOrganisation(WHO)haspublishedseveral
editionsofthe"ManualfortheExaminationofHumanSemenand
Sperm-CervicalMucusInteraction",thelastonein2010.
Theconceptof"LowerReferenceLimit(LRL)wasestablishedinthe
lastmanualoftheWHO.
Therearemanyparametersobtainedthroughaspermiogram,the
mostfrequentlystudiedare:
Volume:Thenormalvolumeofanejaculatesampleafter3/5daysof
sexualabstinenceis1.5mlapproximately.Lowervolumesmight
suggesthypospermia.
Color:Spermisusuallyopalescentwhite,slightlyyellow.Whenthe
colorisaltered,itisrecommendedtostudypossiblecauses.
pH:ValueshouldbegreaterthanT.l.Lowervaluesmightbeasign
ofazoospermia(lackofspermatozoa)orchronicinflammatory
processes.
Spermconcentration:Normalvaluesarearound15millionperml
eiaculatedor39millionpercompletesemensample.Whenthese
valuesareloweritcouldindicateOligozoospermia.
Motility:Thepercentageofmotilespermatozoaandprogressively
motileisanalyzed.Theprogressivemotilityvalueshouldbeover
32%,onthecontraryitmightindicateAstenozoospermia.
Vitality:Thepercentageofvitalspermatozoamustbeover58%.
LowervaluescouldindicateAstenozoospermia.
Morphology:Theremightbe4%ormorenormalspermatozoaina
usualspermiogram.Lowerpercentagescouldindicate
teratozoospermia.
10.Normalvalueofhydrogenionsinhuman
fluidsis?
a)35meq/L
b)40meq/L
c)45meq/L
d)50meq/L
e)Noneoftheabove
CorrectAnswer-E
Ansis'e'i.e.,Noneoftheabove
Thenormalhydrogenionconcentrationofbloodandotherbody
fluidsisquitelow<0.0001mEq/L)comparedwiththebodyfluid
concentrationsofotherelectrolytes.
Becauseitissolow,hydrogenionconcentrationismeasuredinpH
units,calculatedasthenegativelogarithmoftheconcentrationin
milliequivalentsperliter.
NormalpHrangesfrom7.35to7.45forarterialbloodandfrom7
.31to7.41forvenousblood.
11.
Whichofthefollowingplaymost
importantroleinmemory:
a)Synapticnetwork
b)Electricconductionnetwork
c)Conductivitycircuit
d)Conductivitynetwork
e)None
CorrectAnswer-A
Ans:a.SynapticNet.
[Ref:Ganong25th/283-88;Guyton12th/67;AKJain6th/1039-40]
Synapticnetworkssinglebestanswer"Long-termmemoryinvolves
changesinthestructureofneuronsincludinggrowthofnew
processesandsynapses.
So,totheextentthatyourememberanythingaboutthismaterialon
memorytomorrow,ornextweek,ornextyear,itwillbebecause
structuralchangesinsynapsesarebeginninginyourbrains.
12.CyanidepoisoningblockKinflux&Na
efflux.ButATPreversethiseffect.Sotrue
statement(s)relatedtomechanismof
actionofcyanideis/are:
a)Kinflux&NaeffluxisregulatedbyNa-KATPaseenzyme
b)Kinflux&NaeffluxisregulatedbyNa-Kpump
c)ATPprovideenergyforthischannel
d)Na-KATPasechannelisATPindependent
e)None
CorrectAnswer-A:B:C
Ans:a.Kinflux&NaEffluxIsRegulatedByNa-K-ATpase
Enzymeb.Kinflux&NaEffluxIsRegulatedByNa-Kpumpc.
ATPprovidesenergyforthischannel.
[Ref:Reddy32nd/595;Katzung13th/1010;Guyton12th/357;AK
Jain6th/459;Harrison19th/262e-7]
Cyanide:
Directlypoisonsthelaststepinthemitochondrialelectrontransport
chain,cytochromea3,whichresultsinashutdownofcellularenergy
production.
Thispoisoningresultsfromcyanidehighaffinityforcertainmetals,
notablyCoandFe+++.Cytochromea3containsFe+++,towhich
CN-binds.
CyanidePoisoning:
Itinhibitstheactionofcytochromeoxidase,carbonicanhydrase&
probablyofotherenzymesystem.
Itblocksthefinalstepofoxidativephosphorylation&preventsthe
formationofATP&itsuseasanenergysource.
13.TrueaboutCarbonmonoxidepoisoning:
a)COhas100timesmoreaffinitythan02forHb
b)Causerightsideshiftingof02dissociationcurve
c)Oxygen-haemoglobinsaturationcurvebecomeshyperbolic
shape
d)PulseoximetrycanaccuratelydetectlevelofCO
e)10-15%levelofCOnormallymayoccurinhealthynonsmoker
CorrectAnswer-C
Ans:c.Orygen-haemoglobinsaturationsaturationCurve
BecomesHyperbolicShape
[RefGanong25th/650-51;Guyton12th/352;AKJain6th/431;
httpst/pedclerk.bsd.uchicago.edu/page/(www.nebi.Nlm.nih.
gov)
Carbon-monoxide-poisoning:
Carbonmonoxideshiftstheoxygen-haemoglobinsaturationcurveto
theleftandchangesittoamorehyperbolicshape.
Lessoxygenisavailableforthetissues.
plasmalevelofcarboxyhemoglobinisnormallyquitelow.
Atbaseline,levelsupto3percent,naybeseeninnonsmokers,
whilesmokersmayhavelevelsupto10-15%percent.
LeftshiftofO2-Hbdissociationcurveoccurin-COpoisoningHbF,
myoglobinebdecreaseinbodytemperature.
COhasabout240timestheaffinityofO2forHb;thismeansthatCO
willcombinewiththesameamountofHbas02whentheCOpartial
pressureis240timeslower.
14.Deadspaceisincreasedin:
a)Positivepressureventilation
b)Extensionofneck
c)Anticholinergicdrug
d)Endotrachealtubeintubation
e)Emphysema
CorrectAnswer-A:B:C:E
Ans:a.Positivepressureventilationb.Extensionofneckc.
AntiCholinergicdruge.Emphysema
RefAjayYadav5th/4-5;Ganong25th/632-33;Guyton323;AKlain
6th/421
AnatomicalDeadSpaceIncreasedin:
OIdage
Neckextension
jawprotrusion
Bronchodilators
Increasinglungvolume(moreininspiration)
Atropine(causebronchodilation)
Anaesthesiamask,circuits
Intermittentpositivepressureventilation(IppV)&positiveend
expiratorypressure(PEEP)
AlveolarDeadSpaceincreasedby:
Lungpathologiesaffectingdiffusionatcapillarymembranelike
interstitiallungdisease,pulmonaryembolism,pulmonaryedema&
ARDS
Generalanaesthesia
IPPV
PEEP
HYPotension
15.Whichofthefollowingistrueabout
cardiacinnervation:
a)T1-T5issympatheticsupply
b)Inferior&superiorcervicalganglianotinvolveininnervation
c)Parasympatheticsupplyisfromvagusnerve
d)Greatcardiacnervearisefromsuperiorcervicalganglia
e)InferiorcervicalgangliagivesoffInferiorcardiacnerve
CorrectAnswer-A:E
Ans:a.T1-T5issympathetice.Inferiorcervicalgangliagives
offinferiorcardiacnerve
[Ref:BDC6th/Vol.I267;Grayb40th/982;Guyton12th/178;AKlain
6th/324]
CardiacInnervation
Thecervicalgangliaareparavertebralgangliaofthesympathetic
nervoussystem.
Thecervicalganglionhasthreeparavertebralganglia.
Superiorcervicalganglion(largest)-adjacenttoC2&C3
Middlecervicalganglion(thesmallest)-adjacenttoC6;target:
heart,neck.
Inferiorcervicalganglion.Theinferiorganglionmaybefusedwith
thefirstthoracicgangliontoformasinglestructure,thestellate
ganglionadjacenttoC7.
Themiddlecardiacnerve(greatcardiacnerve),thelargestofthe
threecardiacnerves,arisesfromthemiddlecervicalganglion.
Nervesemergingfromchemicalsympatheticgangliacontributeto
thecardiacplexus.
SymPatheticsupply:T1toT5spinalsegments.
SympatheticpreganglionicfibrespassintothesymPathetictrunkto
superionmiddle&inferiorcardiacganglion
Sympatheticpostganglionicfibrespassesviasuperiormiddle&
inferiorcardiacsympatheticnerves
Parasympatheticsupplytoheartisviatwovagusnerveswiththeir
cellbodieslocatedinthemedullainthenucleusambiguus.
16.Trueaboutcortisollevelinbloodplasma:
a)Morningconcentrationis17-18nmol/d1
b)Morningconcentrationis5-23pg/dL
c)Eveningconcentrationisalmosthalfofmorningconcentration
d)Eveningconcentrationis5-23i.ig/dL
e)None
CorrectAnswer-B:C
Ans:b.Morningconcentrationis5-23microg/dLc.Evening
concentrationisalmostHalfOfMorningConcentration
Eveningconcentrationisalmosthalfofmorningconcentration(a/c
belowreferencevalues).
Cortisolconcentrationat8.00aminmorning5-20mcg/dL(140-550
nmol/L).
17.Saccadicceyemovementiscontrolledby:
a)Parietallobe
b)Prefrontallobe
c)Temporallobe
d)Frontalcortex
e)Occipitallobe
CorrectAnswer-D
Ans:d.Frontalcortex
[RefGanong25th/189,195-96;Guyton12tlt/786;AKJain1115-16]
Normallysaccadicmovementsarevoluntarybutcanbearousedby
peripheralvisualorauditorystimulibystimulationoffrontaleye
fields(area8).
Thusthesemovementsareprogrammedinthefrontalcortex.
Thebilateralfrontaleyefieldsinthispartofthecortexareconcerned
withthecontrolofsaccades,andanareajustanteriortothesefields
isconcernedwithvergenceandthenearresponse.
18.TrueaboutnormalECG:
a)NormalPRintervalis0.12-0.20s
b)PRinternalcorrespondenceinitiationofPwavetoinitiationofR
wave
c)QTinternalcorrespondenceinitiationofQwavetoinitiationofT
wave
d)NormalQRSinterval<0.12s
e)NormalQTcinterval
CorrectAnswer-A:D
Ans:a.NormalPRintervalis0.12-0.20sd.NormalQRSinterval
[Ref:Ganong25th/524;Guyton12th/179-80;ECGmadeEasyby
Hamptot4th/6-71]
ThePRintervalismeasuredfromthebeginningofPwavetothe
beginningofQRScomplex.
AQTcintervallongerthan0.45sislikelytobeabnormal.
NormalQRSintervaldurationisnogreaterthan0.12s.
QTintervalisameasureofthetimebetweenthestartoftheQwave
andtheendoftheTwaveintheheart'selectricalcycle.
19.Whichofthefollowingis/aretrueabout
SIADH:
a)Desmopressinisusedfortreatment
b)Vasopressinlevelisinappropriatelyhigh
c)Plasmaosmolalityishigherthanurineosmolality
d)TedOsmolalityofurine
e)TedOsmolalityofplasma
CorrectAnswer-B:D
Ans:b.VasopressinlevelisinappropriatelyHighd.Ted
Osmolalityofurine
[RefHarrison19th/2280;Ganong25th/698;AKJain6th/673-74]
Desmopressinisveryusefulinthemanagementofdiabetes
insipidus.
SyndromeofInappropriateAntidiureticHormone
Thesyndromeof"inappropriate'hypersecretionofantidiuretic
hormone(SIADH)occurswhenvasopressinisinappropriatelyhigh
relativetoserumosmolality.
Vasopressinisresponsiblenotonlyfordilutionalhyponatremia
(serumsodium<135mmol/L)butalsoforlossofsaltintheurine
whenwaterretentionissufficienttoexpandtheECFvolume,
reducingaldosteronesecretion
Features:
Hyposmolality
Increasedurineosmolality
Urineosmolalitybecomeshigherthanplasmaosmolality
UrinaryNa+exceeds20mEq/L
20.Whichofthefollowingfeature(s)is/are
suggestiveofnehogrnicDIincomparison
tocentralDI:
a)Desmopressinnasalsprayrestoreurineoutputtonormallevel
b)Basalvasopressinlevel>1pg/ml
c)NormalposteriorpituitarybrightspotisnotvisibleonMRIscan
d)Changeinwaterlossduringfluiddeprivationtest
e)None
CorrectAnswer-B
Ans:b.Basalvasopressinlevel>1pg/ml
[RefGanong25th/698;Guyton12th/488-89;AKJain6th/674]
FailuretoProduceADH:"Central"DiabetesInsipidus.
Thetreatmentforcentraldiabetesinsipidusisadministrationofa
syntheticanalogofADH,desmopressin,whichactsselectivelyon
V2receptorstoincreasewaterpermeabilityinthelatedistaland
collectingtubules.
Desmopressincanbegivenbyinjection,asanasalspray,ororally,
anditrapidlyrestoresurineoutputtowardnormal.
ThepolyuriaanilpolydipsiaofnephrogenicDIarenotaffectedby
treatment*ithstandarddosesofDDAVP.
21.Truestateinent(s)aboutOlfactorysystem
:
a)Olfactorymucosacoverupper1/3ofnasalcavity
b)Olfactorypathwaypassesviathalamustoorbitofrontalcortex
c)Adaptationtoodourdeveloponlyafter1-2minutes
d)OlfactoryreceptorsactviacAMP
e)Rateofolfactorynerveimpulseschangeapproximatelyin
proportiontothelogarithmofstimulusstrength
CorrectAnswer-A:B:D:E
Ans.(A)Olfactorymucosacoverupper1/3ofnasalcavity
(B)Olfactorypathwaypassesviathalamustoorbitofrontal
cortex(D)OlfactoryreceptorsactviacAMP(E)Rateofolfactory
nerveimpulseschangeapproximatelyinproportiontothe
logarithmofstimulusstrength
Rateofolfactorynerveimpulseschangeapproximatelyinproportion
tothelogarithmoFstimulusstrength.
Theolfactoryreceptorsadaptabout5O%inthefirstsecondorso
afterstlmulatlan.Thereafter,theyadaptverylittleandveryslowly.
Adaptation:Itdevelopswithinsecondsonminutes,dependingon
thenatureofthesubstance.
Weber-FechnerLawstatesthatthesubjectivesensation(ofodor,
soundorlightintensity)isproportionaltothelogarithmof!the
stimulusintensity''
ThereceptorintheolfactorymucousmembranearecoupledtoG-
proteins.
Olfactoryregions:theUpper1/3oflateralwalls(uptosuperior
concha),correspondingpartofthenasalseptumandtheroofofthe
nasalcavityfromtheolfactoryregion'Here,mucousmembraneIs
palerincolor
22.Vomitingcentre(s)involvedinpost-
operativevomiting
a)Areapostrema
b)Chemoreceptortriggerzone(CTZ)
c)Reticularformationlocatedinmedulla
d)Nucleustractussolitarius
e)Basalganglia
CorrectAnswer-A:B:D
Ans.A,AreapostremaB,Chemoreceptortriggerzone(CTZ)&
D,Nucleustractussolitarius
PostoperativeNauseaandVomiting(PONV):
PONVisdefinedasanynausea,retching,orvomitingoccurring
duringthefirst24-48haftersurgeryinpatients.
Accordingtoourcurrentmodel,thebrainstructuresinvolvedinthe
pathophysiologyofvomitingaredistributedthroughoutthemedulla
oblongataofthebrainstem,notcentralized,lnananatomically
defined'vomitingcentre'.
Suchstructuresincludethechemoreceptortriggerzone(cRTZ),
Locatedatthecaudalendofthefourthventricleinthearea
postrema,andthenucleustractussolitarius(NTS),locatedin
theareapostremaandlowerpons.
PONVcanbetriggeredbyseveralperioperativestimuli,including
opioids,volatileanaesthetics,anxiety,adversedrugreactions,and
motion.
23.Trueaboutspecialanatomyand
Physiologyoflung:
a)Surfactantpreventcollapseofsmallalveoliintolargerone
b)Largeralveolihasmoretendencytocollapsethansmaller
alveoliinabsenceofsurfactant
c)Surfactantdecreasechanceofcollapse
d)Surfactantincreasessurfacetension
e)Withsurfactant,largealveolitendtobecomesmallerand
smalleronestendtobecomelarger
CorrectAnswer-A:C:E
Ans.(A)Surfactantpreventcollapseofsmallalveoliintolarger
one(C)Surfactantdecreasechanceofcollapse(E)With
surfactant,largealveolitendtobecomesmallerandsmaller
onestendtobecomelarger
Upperregionalveolihavelargervolumes.
Alreadyfilledwithairandarelesscompliantcomparedtothoseto
dependentregions
LowsurFacetensionalveoliaresmall-duetothepresenceinthe
fluidliningthealveoliofsurfactant,alipidsurface-tension-lowering
agent.
Surfactantdeficiencyisanimportantcauseofinfantrespiratory
distresssyndrome(IRDS,alsoknownashyalinemembrane
disease.
Surfacetensioninthelungsoftheseinfantsishigher,andthe
alveoliarecollapsedlnmatryareas(atelectasis).
24.Allaretrueaboutacromegalyexcept:
a)IncreasedIGF-1levels
b)Excessivegrowthoccursbeforefusionoftheepiphysesofthe
longbones
c)Somatostatinanaloguescanbeused
d)Growthhormonelevelsincreased
e)Transsphenoidalsurgicalresectionisthepreferredprimary
treatmentforpituitaryadenoma
CorrectAnswer-B
Ans.B.Excessivegrowthoccursbeforefusionofthe
epiphysesofthelongbones
Inacromegaly,IGF-IlevelsareinvariablyhighandreflectaLog-
LinearrelationshipwithclrculatlngGHconcentrations.
Foracromegaly,somatostatinanaloguesandGHreceptor
antagonistsareindicated
Age-matchedserumIGF-Ilevelsareelevatedinacromegaly.
Somatostatinanaloguesareusedasadjuvanttreatmentfor
preoperativeshrinkageoflargeinvasivemacroadenomas.
Transsphenoidalsurgicalresectionbyanexperienced.surgeonis
thepreferredprimarytreatment.
Tumorsofthesomatotrophsoftheanteriorpituitary(pituitary
adenomas)secretelargeamountsofgrowthhormone,leadingto
glgantbmlnchlUrenandacromegalyinadults.
Hypersecretionofgrowthhormoneisaccompaniedby
hypersecretionofprolactinin20-40%ofpatientswithacromegaly.
25.Truestatement(S)is/are:
a)Vasopressinincreaseonlywaterreabsorption,notsolute
reabsorption
b)AldosteroneincreaseNa+reabsorptionfromtubules
c)GlomerularfiltrateofPCThassimilarosmolarityasofplasma
d)UrineishyperosmolarinearlyDCT
e)Generallyurineosmolarityequalstoplasmaosmolarity
CorrectAnswer-A:B:C
Ans(A)Vasopressinincreaseonlywaterreabsorption,not
solutereabsorption(B)AldosteroneincreaseNa+reabsorption
fromtubules(C)GlomerularfiltrateofPCThassimilar
osmolarityasofplasma
Antidiuretichormone(ADH,Vasopressin)increasespermeabilityof
distaltubules(mildaction)andcollectingducts(mainly)to
water)increaseswaterreabsorption.
Aldosteronecausesretentlonofsodlumtromthekidneyand
increasedurinaryexcretionofpotassium;ithaslittleeffectonwater
excretion.
PCT:Theosmolalityoffluidstntubuleisunchangedatapprox.
3(X)mosmie,isotonicityismaintained.
ThetubularfluidenteringtheDCTisalwayshypotonictoplasma.
ThefluidinthedescendinglimboftheloopofHenlebecomes
hypertonicaswatermovesoutofthetubuleintothehypertonic
interstitium.
Intheascendinglimbltbecomesmoredilutebecauseofthe
movementofNa+andCl-outofthetubularlumen,and.whenfluid
reachesthetopoftheascendinglt.
AdrenalmineralocorticoidssuchasaLDosteroneincreasedtubular
reabsorptionofNa+inassociationwithsecretionofK+andH+and
alsoNa+reabsorptionwithCl-.
26.Rapidlyadaptingreceptor(s)is/are:
a)Painreceptor
b)Paciniancorpuscles
c)Musclespindle
d)Golgitendonorgans
e)Meissnercorpuscles
CorrectAnswer-B:D:E
Ans.(B)Paciniancorpuscles(D)Golgitendonorgans
(E)Meissnercorpuscles
Rapidlyadapting:Rapidlyadaptingmechanoreceptorsinclude
Meissnercorpuscleend-organs,Paciniancorpuscleend-organs,
hairfolliclesreceptorsandsomefreenerveendings.
Merkel'sdiscsandMelssner'scorpusclesaretactilereceptors.
Theyarerapidlyadaptingreceptors.
Paciniancorpuscles:Theyrespondtodeformationcausedbyfirm
pressureandarequietlyadapting.
27.Whichofthefollowingis/aretrueabout
normallevel:
a)TotalCalcium:8.5-10.5mg/dL
b)Sodium:135-145mmol/L
c)Potassium:3.5-5.1mmol/L
d)Creatinine:0.6-2.6mg/dL
e)TSHlevel:0.1-3.1mIU/L
CorrectAnswer-A:B:C
Ans.(A)TotalCalcium:8.5-10.5mg/dL(B)Sodium:135-145
mmol/L(C)Potassium:3.5-5.1mmol/L
Davidson22ed/1308,HarrisonL9rh/2762,2763,
TSH-.2-4.5mU/L
Calcium(total):8.5-10.5mg/dL
Potassium-3.5-5.0meq/L
Sodium-136-146meq/L
Serumcreatinine-0.6-1.6mg/dl
28.TrueaboutActionPotentialinskeletal
musclefibersandnervefibres:
a)Skeletalmusclefibresconductionvelocityis1/4ofthick
myelinatednervefiber
b)Actionpotentialofbothqualitativelysimilar
c)Restingmembranepotentialalmostsame
d)Durationofactionpotentialsameinboth
e)Actionpotentialofbothquantitivelysimilar
CorrectAnswer-B:C
Ans.(B)Actionpotentialofbothqualitativelysimilar
(C)Restingmembranepotentialalmostsame
MuscleActionPotential-ComparisonwithNerveActionPotential
GuytonIlth/89
Restingmembranepotential:about-80to-90millivoltstoskeletal
fibers-thesameaslnlargemyelinatednervefibers.
Durationofactionpotential1to5millisecondstnskeletalmuscle
aboutfivetimesaslongasinlargemyelinatedfibers..
Velocityofconduction:3to5m/sec-about1/13ththevelocityof
conductioninlargemyelinatedteraefibersthatexciteskeletal
muscle.
29.Comprehensionpreservedinwhichofthe
follwingaphasia
a)Broca'saphasia
b)Conductionaphasia
c)Wernicke'saphasia
d)Gobalaphasia
e)Anomicaphasia
CorrectAnswer-A:B:E
Ans.A,Broca'saphasiaB,Conductionaphasia&E,Anomic
aphasia
Repetition
Comprehension ofSpoken Naming
Fluency
Language
Preserved
Wernicke's
Impaired
Impaired
Impaired or
increased
Preserved
Broca's
(except
Impaired
Impaired Decreased
grammar)
Global
Impaired
Impaired
Impaired Decreased
Conduction
Preserved
Impaired
Impaired Preserved
Nonfluent
Preserved
Preserved Impaired Impaired
(motor)transcortical
Fluent(sensory)
Impaired
Preserved Impaired Preserved
transcortical
No
No
Isolation
Impaired
Echolalia Impaired purposeful
speech
Preserved
exceptfor
Anomic
Preserved
Preserved Impaired word-
finding
pauses
Impairedonlyfor
Pureword
spoken
Impaired
Preserved Preserved
deafness
language
Impairedonlyfor
Purealexia
Preserved Preserved Preserved
reading
30.Tissueelevationofwhichofthefollowing
causevasoconstriction:
a)Na+
b)K+
c)Mg
d)Ca2+
e)H+
CorrectAnswer-D
Ans.D.Ca2+
VascularControlbylonsandOtherChemicalFactorsGuyton
12th(SAE)/269
Anincreaseincalciumionconcentrationcausesvasoconstriction.
Anincreaseinpotassiumionconcentration,.withinthephysiological
range,causesvasodilation.
Anincreaseinmagnesiumionconcentrationcausespowerful
vasodilation.
Anincreaseinhydrogenionconcentration(decreaseinpH)causes
dilationofthearterioles.
Anionsthathavesignificanteffectsonbloodvesselsareacetateand
citrate.AnIncreaseincarbondioxideconcentrationcausesmoderate
vasodilationinmosttissuesbutmarkedvasodilationinthebrain.
31.Whichofthefollowingstatement(s)is/are
truechangesattimeofovulation:
a)GnRHleveldecreases
b)Gonadotropinhormonesurge
c)hCGsurge
d)1`Prostaglandins
e)Activationofproteolyticenzymes
CorrectAnswer-B:D:E
Ans.B,GonadotropinhormonesurgeD,1`Prostaglandins&
E,Activationofproteolyticenzymes
Ovulation:
ThemidcycleLHsurgeisresponsibleforadramaticincreasein
localconcentrationsofprostaglandinsandproteolyticenzymesin
thefollicularwall.
Thesesubstancesprogressivelyweakenthefollicularwalland
ultimatelyallowaperforationtoform.
Ifpregnancydoesoccur,placentalhCGwillmimicLHactionand
continuallystimulatethecorpusluteumtosecreteprogesterone.
FeedbackEffects:
At36-48hbeforeovulation,theestrogenfeedbackeffectbecomes
positive,andthisinitiatestheburstofLHsecretion(LHsurge)that
producesovulation.
Ovulationoccursabout9afterLHpeak-FSHsecretionalsopeaks,
despiteasmallriseininhibin,probablybecauseof.thestrong
stimulationofgonadotropesbyGnRH.
Duringthelutealphase,thesecretionofLHandFSHislowbecause
oftheelevatedlevelsofestrogen,progesterone,andinhibin.
32.Whichofthefollowingstatementsaretrue
regardingdiffusionofgasinlung-
a)Diffusionofgasisperfusionlimited
b)CO,diffuses20timesfasterthan02
c)PO2gradientislowbetweenalveoli&bloodvesselincaseof
restrictivelungdisease
d)Diffusionofgasisdecreasedinemphysema
e)Diffusioncapacityof0,is25
CorrectAnswer-A:B:D:E
Ans.(A)Diffusionofgasisperfusionlimited(B)CO,diffuses20
timesfasterthan02(D)Diffusionofgasisdecreasedin
emphysema(E)Diffusioncapacityof0,is25
Ref:Textbookofrespiratoryphysiology3rded/p913
Flow-limit(Perfusion-limited)Vsdiffusion-limitedtransport:
DiffusionofO2,CO2,N2Oacrosstherespiratorymembraneareall
flow(perfusion)limited.
COtransferisdiffusion-limited-Sincecarbonmonoxide(CO)is
takenupbyhemoglobinanditbindssoavidlywithHb.
DiffusionCapacityOfO2-2O-25ml/min/mmHg.
DiffusionCapacityOfCO2-400ml/min/mmHg
CO2diffuses15-20timesfasterthanO2
Diffusionofgasinemphysema:
EmphysemaCausesthickeningofrespiratorymembrane
Causingreduceddiffusiontogases.
33.Whichofthefollowingaboutrenin
angiotensinsystemaretrue-
a)Reninisproducedbymodifiedsmoothmusclesofglomerular
capillary
b)Maculadensacellsarepartofthispathway
c)Angiotensinogenisconvertedtoangiotensinbythispathway
d)Angiotensinconvertingenzymeispresentinlungcapillary
endothelialcell
e)Angiotensin-IIisdecapeptide
CorrectAnswer-A:B:C:D
Ans.(A)Reninisproducedbymodifiedsmoothmusclesof
glomerularcapillary(B)Maculadensacellsarepartofthis
pathway(C)Angiotensinogenisconvertedtoangiotensinby
thispathway(D)Angiotensinconvertingenzymeispresentin
lungcapillaryendothelialcell
Ref:Principlesofmedicalphysiologyp.417Ganong25th/ep.
672-700
Juxtaglomerularapparatus:
ThejuxtaglomerularaPParatusislocatedattheangleoftheafferent
andefferentarterioles,whereitcomesincontactwiththedistal
tubules.
Itcomprisesthemaculadensa,juxtaglomerular(JGcells),andthe
laciscells.
Juxtaglomerular(granular)cellsaremodifiedsmoothmusclecellsin
thescalamediaoftheterminalpartoftheafferentarterioles.
Theycontainlargegranulesandsecreterenin.
Laciscells(extraglomerularmesangialcells)thatarelocatedinthe
angularspacebetweenthejunctionofafferentandefferent
arterioles&alsocontainsomerenin.
Thepartofthedistaltubulewhichcomesincontactwiththeafferent
arterioleismadeofaspecializedepitheliumcalledthemacula
densa.
RENIN-ANGIOTENSINSYSTEM:
Reninisaproteaseenzymewhichissecretedbyjuxtaglomerular
(jG)cellsofafferentarterioles.
Mostpowerfulstimulusforreninreleaseisreducedrenalperfusion
pressure
Loweredpressurestimulatereninrelease.
IncreasedNaClindistaltubulesissensedbymaculadensaandthe
signalistransmittedtoJGcells.
ThisresultsindecreasedReninrelease.
OppositeoccurswhendecreasedNaClisdeliveredindistaltubule,
i.e.,increasedreninrelease.
Adenosineisprobablythemediatorofsignal.
JGcellsareinnervatedbysympatheticfibers.Theyreleasereninin
responsetosympatheticdischarge,andbycirculating
catecholamines.
ThereninreleasedfromthejGcellsentersthecirculationandacts
onanalpha2-globulin.
Angiotensinogen(secretedbythelivertoconvertitintoa
decapeptide,angiotensinIbysplittingLeucine-Valinebondof
angiotensinogen.
Theenzymeangiotensinconvertingenzyme(ACE)thenactson
angiotensinIandconvertitintoanoctapeptide,angiotensinII,by
splittingphenylalanine-histidinebondofangiotensinII.
ACEisfoundonthesurfaceofcapillaryendotheliumoflung,
thereforeangiotensinIIisformedonlungcapillaryendothelium.
AngiotensinIIisdegradedintoangiotensinIIIbysplitting
asparagine-argininebondbyaminopeptidase.
34.Trueaboutrenaltubularsystemare?
a)AscendingloopofHenleactivelypumpsChlorideoutoftubule
b)AscendingloopofHenleactivelypumpsCarbonateoutof
tubule
c)DescendingloopofHenleispermeabletowater
d)AscendingloopofHenleisimpermeabletowater
e)DescendingloopofHenlereceiveshypotonicsolution
CorrectAnswer-A:C:D
Ans.(A)AscendingloopofHenleactivelypumpsChlorideout
oftubule(C)DescendingloopofHenleispermeabletowater
(D)AscendingloopofHenleisimpermeabletowater
Ref:Ganong25th/ep.680-682
Thindescendingsegment(limb):
Highlypermeabletowater.
Waterabsorptionisobligatoryandoccursthroughaquaporin-1water
channel.
Relativelyimpermeabletosolutes(sodium,chlorideandurea).
Therefore,onlywaterisreabsorbedfromthethindescendingHenle
hypertonicfluid.
Noactivesecretionorreabsorption.
Thinascendingsegment(Limb):
LesspermeabletowaterbutisverymuchpermeabletoNacl.
Thickascendingsegment(limb):
Totallyimpermeabletowater.
Hypotonictoplasma.
Hence,Dilutingsegment.
30%offilteredNa-isreabsorbedinascendinglimb(60%,
reabsorbedinproximaltubule).
35.Truestatementaboutnervemuscle
physiologyis?
a)ActionpotentialtraversesalongTtubules
b)Contractionismainlybecauseofextracellularcalcium
c)Rynadinereceptorssensetheactionpotiential
d)actinpullsthemyosin
e)ATPbindstomyosin
CorrectAnswer-A:C:E
Ans.(A)ActionpotentialtraversesalongTtubules
(C)Rynadinereceptorssensetheactionpotiential(E)ATP
bindstomyosin
Excitationcontractioncoupling:
SkeletalmusclefiberisinnervatedbyA-alphaneuron.
Carriestheimpulse(actionpotential)toneuromuscularjunction
wherereleaseofacetylcholinefrompresynapticvesicleoccurs.
Events:
EachsarcomerehasT-tubules.
T-tubuledepolarizes,conformationalchangesoccurin
dihydropyridineReceptors(DHPR)ofT-tubules.
LeadstoaninteractionbetweenDHPRandRyanodinereceptors
(RyR)intheterminalcisternsofsarcoplasmicreticulum.
DHPR-RyRinteractionleadstoreleaseofCa+ionsfromthe
terminalcisternsintothecytoplasm(sarcoplasm).
DiffusionofCa+intosarcoplasmcausesmuscleContraction.
Molecularevents:
Cross-bridgecycle:
Cross-bridgingofmyosinwithactinproducesbending(flexion)of
myosinheadproduces"Powerstroke"slidingofactinonmyosin
andmusclecontraction.
36.Trueaboutcoppermetabolismisare?
a)Intestinalabsorptionoccursinduodenum
b)95%bondtoalbuminintheserum
c)Ceruloplosmincontains6atomsofcopper
d)FailuretoSynthesizeceruloplasmincauseswilson'sdisease
e)Copperexcretionmainlyoccursinurine
CorrectAnswer-A:C:D
Ans.(A)Intestinalabsorptionoccursinduodenum
(C)Ceruloplosmincontains6atomsofcopper(D)Failureto
Synthesizeceruloplasmincauseswilson'sdisease
Ref:Dineshpuri3ed/p.412
Copperprimarilyfunctionsasacomponentofmetalloenzymesor
proteinsthatparticipateinredoxreactions.
Adulthumanbodycontains50-100mgofcopperofwhichlargest
amountarepresentinmuscles(30-50mg),bones(10-20mg),and
liver(10-15mg).
Absorption:
Intestinalabsorptionofcopperoccursmainlyfromduodenum.
SignificanceofCeruloplasmin:
Fromportalcirculation,copperistransportedtoliver,bindto
albumin,withinhepatocytescopperisincorporatedinto
apoceruloplasmintoformceruloplasmin.
Ceruloplasmincontains6-8atomsofcopper.
Failuretosynthesizeceruloplasminisimplicatedinpathogenesisof
wilsondisease.
Transportandexcretion
Plasmaconcentrationofcopperis100-200mg/dl,about95%of
whichisboundtoceruloplasmin,
Excretionofcoppermainlyoccursinbile.
37.Trueaboutgasequation-
a)Gasconstantis0-9
b)PV=constant
c)PV=nRT
d)Diffusionisdirectlyrelatedtomolecularweightofgas
e)Oxygenhasmorediffusioncoefficient
CorrectAnswer-C
Ans.C.PV=nRT
Gasequation:
Theidealgaslawisquantitativeexpressionoftheforegoing
principles:PV=nRT.
WherePisthepressure,Visthevolume,nisthenumberofgram
moleculesofthegas,RisthegasconstantandTistheabsolute
temperature.
ValueofRis0.082(R=0.082),whentheunitsemployedare
atmosphere,litresandcentigrade.
Therateofinfusion(D)isdirectlyproportionaltothepressure
gradient(LP)andgasdiffusesfromhigherpressureareastolower
pressureareas.
Partialpressuregradient(gaspressuredifference)isthebasicfactor
whichpromotediffusionofagas.
Rateofdiffusionisdirectlyproportionaltootherfactorsalso,viz.(i)
Surfaceareaofrespiratorymembrane(A);and(ii)Solubilityofgas
concerned(S).
Therateofdiffusionisinverselyproportionalto(i)Thethicknessof
therespiratorymembrane(d);and(ii)Molecularweightofthegas
(MW).
38.TrueaboutProstaglandins-
a)Derivedfromlipooxygenasepathway
b)FirstproductisPGG2
c)PGE2causesvasoconstriction
d)PGF2acausesbronchoconstriction
e)PG12causesfallinBP
CorrectAnswer-B:D:E
Ans.(B)FirstproductisPGG2(D)PGF2acauses
bronchoconstriction(E)PG12causesfallinBP
Prostaglandins(PG)synthesis:
Prostaglandins(PGs),thromboxanes(TXs),prostacyclin(PGI)and
leukotrienesarecollectivelycalledeicosanoids.
Thesesarederivativesofprostanoicacid.
Theseeicosanoidsarederivedfrom5,8,11,14eicosatetraenoic
acid(arachidonicacid),thefattyacidreleasedfrommembranelipids
bytheactionofphospholipase-A2.
39.Whichis/arefeature(s)ofprostaglandins-
a)20carbonatomcompound
b)10carbonatomcompound
c)Cyclopentanering
d)-OHgroupat156position
e)Transdoublebondat10thposition
CorrectAnswer-A:C:D
Ans.(A)20carbonatomcompound(C)Cyclopentanering(D)-
OHgroupat156position
(Ref:HarperjP/ep.239-40;Lippincott6h/ep.213-15;Vasudevan
5th/ep.167;Shinde7/ep.64-65;Satyanarayan4th/ep.664)
Prostaglandinsare20carboncompounds,containinga
cyclopentanering.Theyhavehydrox(OH)groupatposition-15and
trans-doublebondatposition-13.
40.
Whichofthefollowingis/areeffectof
increased2,3-DPGonoxygen-hemoglobin
dissociationcurve?
a)edaffinityofheamoglobintooxygen
b)edaffinityofhaemoglobintooxygen
c)Leftshiftofoxygen-hemoglobindissociationcurve
d)Rightshiftofoxygen-hemoglobindissociationcurve
e)Nochangeinoxygen-hemoglobindissociationcurve
CorrectAnswer-B:D
Ans.(B)edaffinityofhaemoglobintooxygen(D)Rightshift
ofoxygen-hemoglobindissociationcurve
[Ref:Ganong25th/ep.610-41;Guyton's12'h/ep.j56-57;AKlain
6'h/ep.430]
Oxygen-hemoglobindissociationcurveis2,3DPGinRBC.
DPGisanoptionalby-productoftheglycolyticpathway.
DPGbindswithdeoxygenatedhemoglobinbutnotwithoxygenated
hemoglobin.
RaisedDPGconcentrationreleasesoxygenfromoxyhemoglobinby
shiftingthefollowingreversiblereactiontotheright.
Mechanism:
OnemoleculeofDPGbindswithonemoleofdeoxyhemoglobin.
HenceanincreaseinDPGconcentrationshiftstheoxygen-
hemoglobindissociationcurvetotheright.
Thus2,3DPGcausesdelivery(unloading)ofO,tothetissues.
Fetalhemoglobinhasconsiderablylessaffinityfor2,3-DPGthan
doesadulthemoglobinthereforefetalhemoglobinhasagreater
affinityforoxygenthanadulthemoglobin.
Inhumanblood,theaffinityoffetalhemoglobinfor2,3-DPGisonly
about4O%thatofadulthemoglobin.
Thismakesfetalhemoglobinbehaveasif2,3-DPGlevelsarelow.
41.Oxygenconsumptionbytheheartis
determinedby?
a)Intramyocardialtension
b)Contractilestateofthemyocardium
c)Initiallengthofthemyocardialmusclefiber
d)Heartrate
e)Basaloxygenconsumptionofmyocardium
CorrectAnswer-A:B:C:D:E
Ans.(A)Intramyocardialtension(B)Contractilestateofthe
myocardium(C)Initiallengthofthemyocardialmusclefiber
(D)Heartrate(E)Basaloxygenconsumptionofmyocardium
[Ref:Ganong25th/ep.550;Guyton's12th/ep.216-17]
Myocardialoxygendemand-Factorsinfluencing:
Thebasalmetabolismofthehearttissuenormallyaccountsof25%
ofmyocardialoxygendemandinrestingindividuals.
Myocytescontraction(cardiaccontraction)istheprimaryfactor
determiningmyocardialoxygenconsumptionabovethebasalleyek
andcardiaccontractionaccountsfor75%ofmyocardialoxygen
consumption.
Myocardialwalltension,
Heartrate(Chronotropy),
Inotropicstate(contractility).
Myocardialwalltensionisdirectlyproportionaltointraventricular
pressure(P)andventricularradius(R)'andinverselyproportionalto
myocardialwallthickness(myocardialmass).
Intraventricularpressure(intracavitarypressure)isdeterminedby
aorticpressure(i.e.,afterload)andventricularradiusisdetermined
byenddiastolicventricularvolume(i.e.,Preload).
42.Insulincausesintracellularshiftofwhich
ofthefollowingion?
a)Na+
b)K+
c)Chloride
d)Calcium
e)Bicarbonate
CorrectAnswer-B
Ans.B.K+
[Ref:Ganong25th/ep.433-34;Guyton's12'h/ep.613;AKlain
6,h/ep.748]
InsulinlowersserumK+concentrationi.e.,causeshypokalemia.
ThehypokalemicactionofinsulinisduetostimulationofK+intake
bythecellsmainlyinmuscleandadiposetissue.
InsulinincreasestheactivityofNa+-K+ATPaseincellmembrane,
sothatmoreK+ispumpedintocells.
43.Hypothalmkpituitaryaxis(HPA)controls
allexcept-
a)Thyroid
b)Parathyroid
c)Pancreas
d)Testis
e)Adrenals
CorrectAnswer-B:C
Ans.(B)Parathyroid(C)Pancreas
[Ref:Ganong25'h/ep.308-14;Harrison'sp.401e-2]
Almostallsecretionbythepituitaryiscontrolledbyeitherhormonal
ornervoussignalsfromthehypothalamus.
Secretionfromtheposteriorpituitaryiscontrolledbynettesignals
thatoriginateinthehypothalamusandterminateintheposterior
pituitary.
Secretionbyanteriorpituitaryiscontrolledbyhormonescalled
hypothalamicreleasingandhypothalamicinhibitoryhormones(or
factors)secretedwithinthehypothalamusandthenconductedtothe
anteriorpituitarythroughhypothalamichypophysealportalvessels.
44.Truestatementaboutmalereproductive
physiology-
a)SertolicellssecreteMiillerianinhibitingsubstance(MIS)
b)Inhibinisreleasedbysertolicell
c)Primaryspermatocyteisdiploid
d)LHandFSHaresteroidalinnature
e)Inhibinstimulatesfollicle-stimulatinghormone(FSH)
CorrectAnswer-A:B:C
Ans.(A)SertolicellssecreteMiillerianinhibitingsubstance
(MIS)(B)Inhibinisreleasedbysertolicell(C)Primary
spermatocyteisdiploid
HormonesoftheTestes:
Thehormone-secretingcellsinthetestesaretheleydigcellsand
sertolicells.
LeydigcellshavereceptorsforLHandsecretealltheandrogens,
i.e.,testosterone(majorandrogen),dihydrotestosterone(DHT),
androstenedioneanddehydroepiandrosterone(DHEA).
Allofthemhave19carbonatoms.
SertolicellsareunderthecontrolofFSH,i,e.,havereceptorsfor
FSH.WhenstimulatedbyFSH,thesecellssecrete
androgenbindingprotein(ABP),inhibinand,MlS(mullerianinhibiting
substance).Sertolicellsalsocontainaromatase;
theenzymethatconvertsandrogenstoestrogens.
Besidethesehormonalfunction,junctionbetweenadjacentsertoli
cellsformsblood-testisbarrierwhichdoesnotallowharmful
substancestoentertheareawherespermatogenesisisgoingon.
Sertolicellakohaverec4,torsforandrogens(testosterone)which
stimulatesspermatogenesis.
Hormonalcontroloftesticularfunction.
LHistropicforleydigcellsandthesecretionoftestosteroneisunder
thecontrolofLH.
FSHistropicforsertolicelland,stimulatessertolicellstosecrete
inhibinandandrogenbindingprotein(ABP).
Primaryspermatocyteisdiploid.
45.Erythropoietinis/areproducedby-
a)Juxtaglomerularcells
b)Interstitialcellsoftheperitubularcapillarybedofthekidneys
c)ParsrectaofPCT
d)Maculadensa
e)Mesangialcell
CorrectAnswer-B
Ans.B.Interstitialcellsoftheperitubularcapillarybedofthe
kidneys
[Ref:Ganong25e/ep.706;Guyton's12e/ep.461;AKlain6e/ep.
68]
Erythropoietinisaglycoproteinhormonewhichstimulateerythrocyte
production.
Inadults,about85%oferythropoietincomesfromthekidney
(interstitialcellsinperitubularcapillarybed)and15%fromliver
(Perivenoushepatocytes).Smallamountisalsoproducedinbrain;
anduterusandoviduct.
46.Trueaboutcarotidsinus-
a)Chemoreceptor
b)Presentinearlypartofinternalcarotidartery
c)Hasglomuscells
d)Baroreceptor
e)Suppliedbyglossopharyngealnerve
CorrectAnswer-B:D:E
Ans.(B)Presentinearlypartofinternalcarotidartery
(D)Baroreceptor(E)Suppliedbyglossopharyngealnerve
[Ref:Ganong25th/ep.658;Guyton'sl2h/ep.251-52;AKlain6th/ep.
j27-29;Gray,s4p/ep.447]
Carotidsinusisalittlebulgeattherootofinternalcarotidartery,
Isatypeofabaroreceptor.
Itisinnervatedbythesinusnerve,abranchofglossopharyngeal(IX
cranial)nerve.
47.Stresshyperglycemiaoccursduetoall
except-
a)IncreasedlevelofACTH
b)Increasedlevelofcortisol
c)Decreasedlevelofnorepinephrine
d)Insulinresistance
e)Increasedlevelofepinephrine
CorrectAnswer-C
Ans.C.Decreasedlevelofnorepinephrine
[Ref:Ganong25th/ep.364;Guytan's12'h/ep-598-556;Schwartz
th/ep.17-2a;AKlain6'h/ep.606;Bailey6Love2Ch/ep.4'9;
CSDT1l'h/ep.103-05]
StressHyperglycemia:
Suppressionofinsulinsecretioncoupledwithincreasedsecretionof
glucagon,growthhormone,glucocorticoids(cortisol),and
catecholamines(epinephrine,
norepinephrine)leadstohyperglycemia.
48.Parasympatheticnervestimulationresults
in:
a)Sphincterclosureofgallbladder
b)Increasedperistalsis
c)DecreasedGITmotility
d)Detrusormusclerelaxation
e)Gallbladdermusculaturecontraction
CorrectAnswer-B:E
Ans.(B)Increasedperistalsis(E)Gallbladdermusculature
contraction
[RefGanong25th/257-60,24th/265;Katzung13th110-111]
Parasympatheticnervesaremotortomusculatureofthegallbladder
&bileduct,butinhibitorytothesphincter.
SympatheticnervesfromT7-9arevasomotor&motortosphincters.
Thecranialoutflowoftheparasympatheticdivisionsuppliesthe
visceralstructuresintheheadviaoculomotor,facial,and
glossopharyngealnerves,andthoseinthethoraxandupper
abdomenviathevagusnerves.
Pupil-Constricted(Miosis)
Ciliarymuscle-Constricted(nearvision)
Glands(Nasal,Lacrimal,Parotid,SubmandibulalGastricPancreatic)
-Stimulationofcopioussecretion(containingmanyenzymesfor
enzyme-secretingglands)
Sweatglands-Sweatingonpalmsofhands
Bronchialmuscle-Contraction
Gallbladderandbileducts-Contracted
LUmen-Increasedperistalsisandtone
Detrusor-Contracted
Trigone-Relaxed
49.Trueaboutmusclespindle:
a)GroupIafibercontainsensoryafferent
b)Nuclearbag&nuclearchainfiberspresentinintrafusalmuscle
fiber
c)MotorsupplybyAafiber
d)Motorsupplybyyfiber
e)Secondaryendingisstimulatedbynuclearbagfiber
CorrectAnswer-A:B:D
Ans.(A)GroupIafibercontainsensoryafferent(B)Nuclear
bag&nuclearchainfiberspresentinintrafusalmusclefiber
(D)Motorsupplybyyfiber
[Ref.A.K.Jain6th/873-76;Guyton12th/770-73]
MUSCLESPINDLES
Are"Stretchreceptor"locatedwithinamuscle.
Yetfound,interminglingwithmusclefibers.
'Intrafusalfibers'-Specializedmusclefibersseenwithin
spindle
(Note:-Fususreferstospindle).
Nuclearbagfibers:
Usually,2perspindle.
Nuclearbagfiber1-
WithlowlevelofmyosinATPaseactivity.
Nuclearbagfiber2-
WithhighlevelofmyosinATPaseactivity.
Nuclearchainfibers
Arethinner&shorter.
Fourormorefibersperspindle(morethannuclearbagfibers)
Sensory/afferentinnervation:
Twoafferentfibertypesoriginateintrafusally,
Annulospiral/primaryendings:
Foundwoundaroundcentralregionofbothnuclearbag&nuclear
chainfiber.
Are"A"/"Ia"fibers.
Flower-spray/secondaryendings:
Innervateperipheralparts/endsofnuclearchainfiber.
Are"A"/"II"fibers.
2.Motor/efferentinnervation:
Innervatesperipheralpartsofbothnuclearbag&nuclearchain
fibers.
Mainlyby"A"type/"-motorneurons"/"Fusimotorneuron"/"Small
motornervesystemofLeksellefferents".
Becauseoftheircharacteristicsmallersize.
50.Hyperbaricoxygentherapyis/areusedin:
a)Radiationinducedproctitis
b)Tensionpneumothorax
c)Bleomycininducedlungdamage
d)Gasaangrene
e)Carbonmono-oxidepoisoning
CorrectAnswer-A:D:E
Ans.(A)Radiationinducedproctitis(D)Gasaangrene
(E)Carbonmono-oxidepoisoning
[RefManipalsurgeryp.176;A.K.Jainp.461]
HyperbaricOxygenTherapy-Indication:
Anaemichypoxiaespeciallyduetocarbonmono-oxidepoisoningor
severebloodloss)
Stagnanthypoxia
Histotoxichypoxia(Radiationinducedtissueinjury&gasgangrene)
COpoisoning.
Infection(gasgangrene).
Cancertherapytopotentiatercdiathcrapy
Arterialinsufficiency
Decompressionsickness&airembolism
Contraindication-
Untreatedpneumothorax
Duringtreatmentwithdrugslike-Bleomycin(bleomycin-induced
lung
injury),Doxorubicin(Adriamycin),cisplatin,Disulfiram.
51.Peripheralcyanosisis/areassociated
with:
a)SLE
b)TAPVC
c)Atrialseptaldefect
d)Methemoglobinemia
e)Cardiogenicshock
CorrectAnswer-E
Ans.E.Cardiogenicshock
[Ref:PJM20th/16-19;Ganong25th/642.]
Peripheralcyanosis:
Causedbyslowingofbloodflowandincreasedextractionofoxygen
fromnormallysaturatedblood.
Resultsfromvasoconstrictionordecreasedperipheralbloodflow,
reducedcardiacoutputorvascularocclusion.
Characterizedbycyanosisofskinaloneandsparingofmucous
membranes
Causes:
Vasculorocclusion
Arterialobstruction
Venousobstruction
Reducedcardiacoutput
Coldexposure
Redistributionofbloodflowfromtheextremities
52.Bloodinfoetusis/areformedby:
a)Liver
b)Lymphnodes
c)Spleen
d)Bonemarrow
e)Yolksac
CorrectAnswer-A:B:C:D:E
Ans.(A)Liver(B)Lymphnodes(C)Spleen(D)Bonemarrow
(E)Yolksac
Bloodformationoccurlater(5wk)throughoutembryonic
mesenchyme,thenliver,spleen/thymus,bonemarrowlymphnode
(ref:embryoIogy.mrd.unsw.au).
FormationofbloodincludeformationofRBC,WBC&platelet.
Bloodproductionstartsfrom3rdweekofintrauterinelife.
3rdweekto3rdmonth(intravascularphase)-Erythropoiesisoccurs
inthemesodermofyolksac
B/w3rdto5thmonthofintrauterinelife,erythropoiesisoccur
principallyintheliver(tosomeextentinthespleen).
5thmonthonwards(myeloidphase)=Erythropoiesisoccursinred
bonemarrow(allmarrowisredbonemarrowatthisstage)
53.Importantbuffersystemoperatingin
blood:
a)Proteinsystembuffer
b)Phosphatebuffer
c)Carbonicacid-Bicarbonatesystembuffer
d)Hemoglobinsystembuffer
e)None
CorrectAnswer-A:C:D
Ans.(A)Proteinsystembuffer(C)Carbonicacid-Bicarbonate
systembuffer(D)Hemoglobinsystembuffer
[RefA.K.Jain6th/559-60,55;Ganong25th/643-44]
Acidandbaseshiftsinthebloodarelargelycontrolledbythreemain
buffersinblood:(1)proteins,(2)hemoglobin(3)thecarbonicacid-
bicarbonatesystem
Morethan90%ofblood'scapacitytobuffercarbonicacidis
attributedtothehaemoglobinbuffersystem.
Carbonicacid-bicarbonatesystemisoneofthemosteffectivebuffer
systemsinthebody.
Inplasma,phosphateconcentrationistoolowforthissystemtobea
quantitativelyimportantbuffetbutitisimportantintracellularly.
54.Pepsinogen,theinactiveformofpepsin,
issecretedby:
a)InterstitialcellofCajal
b)Chiefcell
c)Panethcell
d)Gobletcell
e)ZymogenCells
CorrectAnswer-B:E
Ans.(B)Chiefcell(E)ZymogenCells
[RefGanong25th/456,24th/457-59]
Thegastricmucosacontainsmanydeepglands.
Inthepyloricandcardiacregions,theglandssecretemucus.
Bodyofthestomach,includingthefundus,theglandscontain
parietal(oxyntic)cells,whichsecretehydrochloricacidandintrinsic
factor,andchief(zymogen,peptic)cellssecretingpepsinogen.
55.TypeIIBmusclefibersaredifferentfrom
typeIfiberwithhaving:
a)Smalldiameter
b)CalciumreWleasebysarcoplasmicreticulumislow
c)Fastfatigable
d)Colorpink
e)Fasteracting
CorrectAnswer-C:E
Ans.(C)Fastfatigable(E)Fasteracting
[RefGanong25th/108,24th/107t23rd/103]
ClassificationErlanger Lloyd&
Characteristics Function
&Gasser
Hunt
offibers
Diameter-13-
20
Myelination
Proprioception-
-Heavily
Duetofiberthickness
myelinated&
Motorsupplyto
Aalpha
I
thick
skeletalmuscle
Conduction-
(extrafusalto
70-120
musclespindle)
(maximum
velocity)
Diameter-4-13
Myelination-
Touch
Abeta
II
Present
Kinesthesia
Conduction-
Pressure
25-70
-No
comparable
ent
Diameter-3-6
Diameter- Myelination-
Motorsupplyto
3-6
Slightly
intrafusalmuscle
Agamma
Myelination myelinated
fibers(Muscle
-Slightly
Conduction-
spindles)
myelinated 15-30
Conduction
-15-30ity-
Pain-
Diameter-1-5 "Fast/Epicritic/First"
Myelination-
pain.
Some
Sincefibersare
Adelta
III
myelination
relativelyfast
Conduction-5- Temperature
30
Pressure
Touch
Diameter-1-3
Myelination-
Preganglionic
-No
Some
autonomicfibers
Bfiber
comparable myelination
(bothsympathetic&
entity-
Conduction-3- parasympathetic)
14
Pain-
Diameter-0.2- Slowpain
1.0
("Protopathic
Myelination-
/Secondpain)
Cfiber
IV
Unmyelinated Temperature
Conduction-
Pressure
0.2-2
Postganglionic
(minimum)
autonomicfibers.
56.Whichofthefollowingistrueabout
myoglobin:
a)Bind1molofoxygenpermoleofmyoglobin
b)Dissociationcurveisarectangularhyperbola
c)Itscurveliesrightofthehemoglobincurve
d)BindoxygenatlowP02pressure
e)ShowBohreffect
CorrectAnswer-A:B:D
Ans.(A)Bind1molofoxygenpermoleofmyoglobin
(B)Dissociationcurveisarectangularhyperbola(D)Bind
oxygenatlowP02pressure
RefGanong25th/641-42,24th/643-zt4;Guyton12th/96
Myoglobin:
Iron-containingpigmentfoundinskeletalmuscle.
Containsonehemegroupwithonepolypeptidechain.
Resembleshemoglobin,butmyoglobinbinds1ratherthan4molof
O2mole.
Itsdissociationcurveisarectangularhyperbolaratherthana
sigmoidcurve.
?Becauseit'scurveistotheleftofthehemoglobincune,asittakes
upO2fromhemoglobinintheblood.
DoesnotshowBohreffect.
57.Vasomotorinputstorostralnuclesusof
ventomedialmedullais/arefrom:
a)Inhibitoryinputfromcaudalventrolateralmedulla
b)Excitatoryinputsfromcerebralcortexviahypothalamus
c)Inhibitoryinputsfromcerebralcortexviahypothalamus
d)Inhibitoryinputsfrombrainstemreticularformation
e)Inhibitoryinputspainpathway
CorrectAnswer-A:B:C
Ans.(A)Inhibitoryinputfromcaudalventrolateralmedulla
(B)Excitatoryinputsfromcerebralcortexviahypothalamus
(C)Inhibitoryinputsfromcerebralcortexviahypothalamus
[RefGanong25th/587-89,24th/589-91]
Medullarycontrolofthecardiovascularsystem:
OneofthemajorsourcesofexcitatoryinPuttosympatheticnerves
controllingthevasculatureisagroupofneuronslocatednearthe
pialsurfaceofthemedullaintheRostralVentrolateralMedulla
(RWM).
Thisregionissometimescalledavasomotorarea
NeurovascularcompressionoftheRVLMhasbeenlinkedtosome
casesofessentialhypertensioninhumans
TheactivityofRVLMneuronsisdeterminedbymanyfactors
FactorsaffectingtheactivityofRVLM
Excitatoryinputs:
Cortexviohypothalamus,mesencephalicperiaqueductalgray,brain
stemreticularformation,painpathway,somaticafferent
(somatosympatheticreflex),Carotid&aorticchemoreceptors
Inhibitoryinputs:
Cortexvidhypothalamus,caudalventrolateralmedulla,caudal
medullaryraphenuclei,lunginflationafferents;carotid,aortic&
cardiopulmonarybaroreceptors
58.ForGrowthhormonetesting,whichofthe
followingstimulatethesecretionsof
Growthhormone:
a)Glucagon
b)Insulin
c)Cortisol
d)Waterdeprivation
e)Arginine
CorrectAnswer-A:E
Ans.(A)Glucagon(E)Arginine
[Ref:Ganong25th/328-29,24th/330-32;Guyton12th/555-56;]
GHTesting:
StimulateGrowthHormone:
Decreasedbloodglucose
Decreasedbloodfreefattyacids
Increasedbloodaminoacids(arginine)
Starvationorfasting
Proteindeficiency
Trauma
Stress
Excitement
Exercise
Testosterone
Estrogen
Deepsleep(stagesllandlV)
Growthhormone-releasinghormone
Ghrelin
59.Whichofthefollowingarefeatureof
blood-brainbarrier:
a)Thickbasementmembrane
b)Podocyte
c)Closelyassociatedlayerofastrocyte
d)Tightjunction
e)Decreasedvesiclesinendothelialcells
CorrectAnswer-A:C:D:E
Ans.(A)Thickbasementmembrane(C)Closelyassociated
layerofastrocyte(D)Tightjunction(E)Decreasedvesiclesin
endothelialcells
Ref;Ganong25th/671,24th/604-06;Guyton12th/816-17
Blood-brainbarrier(BBB):
Barriersexistbothatthechoroidplexusandatthetissuecapillary
membranesinessentiallyallareasofthebrainparenchymaexcept
insomeareasofthehypothalamus,pinealgland,and.area
postremawheresubstancesdiffusewithgreatereaseintothetissue
spaces.
Causeofthelowpermeabilityoftheblood-brainbarrieristhe
mannerinwhichtheendothelialcellsofthebraintissuecapillaries
arejoinedtooneanother.
Theyarejoinedbyso-calledtightjunctions.
Thatis,themembranesoftheadjacentendothelialcellsaretightly
fusedratherthanhavinglargeslit-poresbetweenthem,asisthe
caseformostothercapillariesofthebody.
Glialcellsarederivedfromneuroectoderm(macroglia:astrocytes,
oligodendrocytes,ependyma)orfrombonemarrow(microglia).
Glialcells(astrocytes)formalayeraroundbrainbloodvesselsand
maybeimportantinthedevelopmentofthe8BB.
Astrocytesmaybealsoberesponsiblefortransportingionsfromthe
braintotheblood
60.Whichofthefollowingstatementis/are
trueregardingFickprincipleof
measurementofcardiacoutput:
a)Cardiacoutputiscalculatedbyamountofoxygenconsumedby
wholebodyperunitmassdividedbyA-VOxygendifference
acrossthelung
b)Oxygenconcentrationinarteryismeasuredbypassingcatheter
toPulmonaryartery
c)Mixedvenousbloodismeasuredbyinsertingcatheterinto
pulmonaryartery
d)Rateofoxygenabsorptionbythelungsismeasuredby
spirometry
e)Foroxygencontentofartery,anyarteryofbodycanbechosen
CorrectAnswer-A:C:D:E
Ans,(A)Cardiacoutputiscalculatedbyamountofoxygen
consumedbywholebodyperunitmassdividedbyA-VOxygen
differenceacrossthelung(C)Mixedvenousbloodismeasured
byinsertingcatheterintopulmonaryartery(D)Rateofoxygen
absorptionbythelungsismeasuredbyspirometry(E)For
oxygencontentofartery,anyarteryofbodycanbechosen
[Ref:Ganong25th/543-44,24th/546-47;A.K.Iain5th/356;Guyton1
lth/244]
CardiacOutputMeasurement:
Fickprinciplestatesthattheamountofasubstancetakenupbyan
organ(orbythewholebody)perunitoftimeisequaltothearterial
levelofthesubstanceminusthevenouslevel(A-Vdifference)times
thebloodflow.
Principlecanbeusedtodeterminecardiacoutputbymeasuringthe
amountofO,consumedbythebodyinagivenperiodanddividing
thisvaluebytheA-Vdifferenceacrossthelungs.
InapplyingthisFickprocedureformeasuringcardiacoutputinthe
humanbeing,mixedvenousbloodisusuallyobtainedthrougha
catheterinsertedupthebrachialveinoftheforearm,throughthe
subclavianvein,downtotherightatrium,and,finally,intotheright
ventricleorpulmonaryartery.
Rateofoxygenabsorptionbythelungsismeasuredbytherateof
disappearanceoforygenfromtherespiredair,usinganytypeof
oxygenmeter(e.gclosecircuitspirometry)
BecausesystemicarterialbloodhasthesameO2contentinallparts
ofthebody,thearterialO2contentcanbemeasuredinasample
obtainedfromanyconvenientartery.
61.Feature(s)ofhyperprolactinemiais/areall
except:
a)Amenorrhoea
b)Decreasemilkproduction
c)Galactorrhoea
d)Hypogonadotropichypogonadism
e)Hypothyroidismmaycausehyperprolactinemia
CorrectAnswer-B
Ans.B.Decreasemilkproduction
[Ref:Ganong25th/331-33,24th/334-35;A.K.Iain5th/695-96;
Guyton11th/907,918-921,I039-40;CMDT2016/1096-97,06/
1113-14]
Hyperprolactinemia:
Duetoanycausemayresultinhypogonadotropichypogonadism.
HypogonadotropichyPogonadismoftendevelopsinpatientswith
hyperprolactinemia;itmaybereversedwithtreatmentof
hyperprolactinemia.
Womenmaynoteoligomenorrhoeaoramenorrhoea.
Galactorrhoea,definedasLactationinabsenceofnursing,is
common.
Prolactindeficiencyinhibitspostpartumlactation.
Primaryhypothyroidismisassociatedwithmildhyperprolactinemia,
probablybecauseofcompensatoryTRHsecretion
62.Whichofthefollowingis/arePainscale:
a)McGillPainQuestionnaire
b)Visualanaloguescale
c)ColouredAnalogueScale
d)Alloftheabove
e)Noneoftheabove
CorrectAnswer-D
Ans.A,McGillPainQuestionnaireB,Visualanaloguescale&
C,ColouredAnalogueScale
ListofPainMeasurementScales:
Wong-BakerFACESPainRatingScale
Visualanalogscale(VAS)
McGillPainQuestionnaire(MPQ)
NeckPainandDisabilityScale-NPAD
Lequesnealgofunctionalindex.
BehavioralPainScale(BPS)
BriefPainInventory(BPI)
ClinicalGlobalImpression(CGI)
Critical-CarePainObservationTool(CPOT)
COMFORTscale
FacesPainScale-Revised(FPS-R)
63.TrueaboutOxytocin:
a)Secretedfromanteriorpituitary
b)Secretedbyposteriorpituitary
c)Decapeptide
d)Gonadotropinreleasinghormone(GnRH)stimulateitssecretion
e)Causemilkejectionbycontractionofmyoepitheliumofbreast
CorrectAnswer-B:E
Ans.(B)Secretedbyposteriorpituitary(E)Causemilkejection
bycontractionofmyoepitheliumofbreast
[Ref:Ganong25th/311-13,24th/311-l3;Guytonp918,1040-41,928]
Oxytocin:
Stimulatespostpartummilkletdowninresponsetosuckling.
Nonapeptide(9aminoacids).
DiffersfromAVPonlyatpositions3and8.
Relativelylittleantidiureticeffectandseemstoactmainlyon
mammaryductstofaci-litatemilkletdownduringnursing.
Mayhelpinitiateorfacilitatelaborbystimulatingcontractionof
uterinesmoothmuscle,butitisnotclearifthisactionisphysiologic
ornecessaryfornormaldelivery.
Gonadotropin-releasinghormone(GnRH):Itissecretedfrom
hypothalamus&stimulatessecretionofFSH&LH.
64.Trueabouthormonesensitivelipase:
a)Activityisincreasedbyinsulin
b)Foundintracellular
c)ActivatedbyEpinephrine
d)Locatedinwallbloodcapillaries
e)None
CorrectAnswer-B:C
Ans.B,Foundintracellular&C,ActivatedbyEpinephrine
[Harper30th/261-62,28th/220]
Hormone-sensitivelipase:
Hormone-sensitivelipaseisactivatedbyACTH,TSH,glucagon,
epinephrine,norepinephrine,andvasopressinandinhibitedby
insulin,prostaglandinE1,andnicotinicacid
Triacylglycerolundergoeshydrolysisbyahormone-sensitivelipase
toformfreefattyacidsandglycerol.
Thislipaseisdistinctfromlipoproteinlipase,whichcatalyzes
lipoproteintriacylglycerolhydrolysisbeforeitsuptakeinto
extrahepatictissues.
65.Whichofthefollowingistrueregarding
GLUT-5:
a)Presentinbrain
b)PresentinAdiposetissue,skeletalmuscle&skin
c)Insulinmediatedtransporter
d)Sodiumindependenttransport
e)PresentinRBC
CorrectAnswer-D
Ans.(D)Sodiumindependenttransport
[Ref:Ganong25th/435,24th/435;Harper30th/191,28th/171;
LippincottBiochemistry4th/97]
GLUT-5isunusualinthatitistheprimarytransporterforfructose
(insteadofglucose)inthesmallintestine&thetestes.
Hassodiumindependentfacilitateddiffusionmechanism.
66.Truestatementrelatingtocomplianceof
lung:
a)Increasedbysurfactant
b)Decreasedinemphysema
c)Atheightofinspirationcomplianceisless
d)Itcanbemeasuredbymeasuringintrapleuralpressureat
differentlungvolume
e)None
CorrectAnswer-A:C:D
Ans.(A)Increasedbysurfactant(C)Atheightofinspiration
complianceisless(D)Itcanbemeasuredbymeasuring
intrapleuralpressureatdifferentlungvolume
[Ref:Ganong25th/629-32,24th/629-33;Guytonllth/473-75;A.K.
Jain5th/437]
Lungcompliance:
Measuredbymeasuringintrapleuralpressureatdifferentlung
volume.
Animportantfactoraffectingthecomplianceofthelungsisthe
surfacetensionofthefilmoffluidthatlinesthealveoli.
Deficiencyofsurfactant-lesscompliance;moresurfactant-more
compliance.
Compliancedecreaseswiththeinflationofthelungsasmore
pressureisrequiredtodistendthealreadydistendedlung.
Thecurveisshifteddownwardandtotheright(complianceis
decreased)bypulmonarycongestionandinterstitialpulmonary
fibrosis;pulmonaryfibrosisisaprogressivediseaseofunknown
causeinwhichthereisstiffeningandscarringofthelung.
Thecurveisshiftedupwardandtotheleft(complianceisincreased)
inemphysema.
67.TrueaboutHering-Breuerreflex:
a)Signalinitiatedthroughmechanoreceptorreceptorsoflung
b)SignalinitiatedthroughChemoreceptoroflung
c)SignalinitiatedthroughCarotid&aorticbody
d)Transmitsignalsthroughthevagusnerve
e)None
CorrectAnswer-A:D
Ans,(A)Signalinitiatedthroughmechanoreceptorreceptorsof
lung(D)Transmitsignalsthroughthevagusnerve
[Ref:Ganong25th/662,24th/664;Guyton12th/372;A.K.lain5th/461,
463,465]
Hering-BreuerinflationReflex-LunginflationSignalsLimit
Inspiration:
Hering-Breuerinflationreflexisanincreaseinthedurationof
expirationproducedbysteadylunginflation,andtheHering-Breuer
deflationreflexisadecreaseinthedurationofexpirationproduced
bymarkeddeflationofthelung.
Inhumanbeings,theHering-Breuerreflexprobablyisnotactivated
untilthetidalvolumeincreasestomorethanthreetimesnormal
(greaterthanabout1.5litersperbreath).
LungInflationSignalsLimitInspiration-TheHerireuerInflation
Reflex:
Stretchreceptorstomechanoreceptorclass.
Stretchreceptors,locatedinthemuscularportionsofthewallsofthe
bronchiandbronchiolesthroughoutthelungs,transmitsignals
throughthevagiintothedorsalrespiratorygroupofneuronswhen
thelungsbecomeoverstretched.
68.Trueaboutbloodsupplyofkidney:
a)Flowis600ml/mineachkidney
b)Itreceivesmorebloodsupplyperunitmassthanthebrain
c)Renalmedullahavemoresupplythanrenalcortex
d)Itisunderdirectsympatheticcontrol
e)None
CorrectAnswer-A:B:D
Ans.(A)Flowis600ml/mineachkidney(B)Itreceivesmore
bloodsupplyperunitmassthanthebrain(D)Itisunderdirect
sympatheticcontrol
[Ref:Ganong25th/602,674,24th/676-77;Guyton12th/466-67]
Essentiallyallthebloodvesselsofthekidneys,includingtheafferent
andefferentarterioles,arerichlyinnervatedbysympatheticnerve
fibers.
Bloodflowtothetwokidneysisnormallyabout22percentofthe
cardiacoutput,or1100mlmin
Theouterpartofthekidney,therenalcortex,receivemostofthe
kidney'sbloodflow.
Bloodflowinrenalmedullaaccountsforonly1to2%ofthetotal
renalflow
Onaper-gram-weightbasis,thekidneysnormallyconsumeoxygen
attwicetherateofthebrainbuthavealmostseventimestheblood
flowofthebrain.
Inarestingadult,thekidneysreceive1.2-1.3Lofbloodperminute,
orjustunder25%ofthecardiacoutput
69.AllaretrueaboutBrunner'sglandexcept:
a)Itliesinduodenumonly
b)Itliesinduodenum&ileum
c)Itsecretesbicarbonaterichfluid
d)ItsecretionsneutralizesacidicpHofstomach
e)Secretesmucusrichfluid
CorrectAnswer-B
Ans.B.Itliesinduodenum&ileum
[RefGuyton12th/400;A.K.lain5th/202-03]
Brunner'sGland:
Sub-mucousglands&aretortuous,long&penetratethemuscularis
mucosa
Drainsintothecryptsoflieberkuhn.
Numerousinfirstpartofduodenum(duodenalcaporbulb)meager
belowthecommonopeningofbile&pancreaticducts.
Ingestionoffattyfoodorsecretininjectionproduceslargevolumeof
thickalkalinemucoussecretionwhichprobablyhelpstoprotectthe
duodenalmucosafromthegastricacid.
Intheduodenumthereareinadditionthesmall,coiledacinotubular
duodenalglands(Brunner'sglands
Functions:
Protectstheduodenalwallfromdigestionbythehighlyacidicgastric
juiceemptyingfromthestomach.
Mucuscontainsalargeexcessofbicarbonateions,whichaddtothe
bicarbonateionsfrompancreaticsecretionandliverbilein
neutralizingthehydrochloricacidenteringtheduodenumfromthe
stomach"
70.Oxygenbindingtohemoglobincause
allostericactivation.Thisallosteric
propertyofHbresultsin:
a)Maintainingironinferrousstate(Fe2+)
b)Increaseoxygensupplytotissue
c)Increasesoxygenbinding
d)Increases2,3-DPGinblood
e)None
CorrectAnswer-B:C
Ans.(B)Increaseoxygensupplytotissue(C)Increasesoxygen
binding
[RefHarper30th/54-55,29th/S0-51;Ganong2STH/639-4I,
24th/64I-44;Guyton12th/353-56;A.KIain5the/p.57]
Theironinhaemlsinfenousstate(Fe2+)form.
EachFe2+combineloosely&reversiblywithonemoleculeof
oxygen.
Combinationofhaemwithoxygeniscalledoxygenation¬
oxidation,becauseaftercombinationwithorygen,ironinhaemstay
inFe2+state
OxygenationofHemoglobinTriggersConformationalChanges
intheApoprotein:
Hemoglobinsbindfourmoleculesof02pertetramer,oneperheme.
AmoleculeofO2bindstoahemoglobintetramermorereadilyif
otherO2moleculesarealreadybound.
Termedcooperativebinding,thisphenomenonpermitshemoglobin
tomaximizeboththequantityofO2loadedatthePO2ofthelungs
andthequantityofO2releasedatthePO2oftheperipheraltissues.
TheAllostericPropertiesofHemoglobinsResultfroMTheir
QuaternaryStructures.
Thepropertiesofindividualhemoglobinsareconsequencesoftheir
quaternaryaswellasoftheirsecondaryandtertiarystructures.
Thequaternarystructureofhemoglobinconfersstrikingadditional
properties,absentfrommonomericmyoglobin,whichadaptsittoits
uniquebiologicalroles.
71.Calcitriolinchildrenisformedin:
a)Glomerulus
b)Bowmanncapsule
c)PCT
d)DCT
e)Collectingduct
CorrectAnswer-C
Ans.(C)PCT
[Ref:Ganong25th/377-78,24th/461Nelson19th/204;A.K.lain
Sth/730:OPGhai8th/112]
Calcitriolisproducedinthecellsoftheproximaltubuleofthe
nephroninthekidneysbytheactionof25-hydroxyvitaminD31-
alpha-hydroxylase,amitochondrialoxygenaseandanenzyme
whichcatalyzesthehydroxylationof25-hydroxycholecalciferol
(calcifediol).
TheactIVItyoftheenzymeisstimulatedbypTH.
ThereactionisanimportantcontrolpointinCa2+homeostasis.
72.Secretionofinsulinisincreasedby:
a)Fattyacid
b)Aminoacid
c)Adrenaline
d)Acetylcholine
e)Somatostatin
CorrectAnswer-A:B:D
Ans.(A)Fattyacid(B)Aminoacid(D)Acetylcholine
[RefGanong25TH/439,24th/441;Guyton12th/615]
IncreaseinsulinSecretion:
Increasedbloodglucose
increasedbloodfreefattyacids
Increasedbloodaminoacids
Gastrointestinalhormones(gastrin,cholecystokinin,secretin,gastric
inhibitorypeptide)
Glucagon,growthhormone,cortisol
Parasympatheticstimulation;acetylcholine
Beta-adrenergicstimulation
Insulinresistance;obesity
Sulfonylureadrugs(glyburide,tolbutamide)
73.Trueaboutcarbohydratemetabolism:
a)Itsupplies4kcalspergram
b)Itincreasesinsulinsecretion
c)Storedinliver
d)Instarvationglycogeninliverisexhaustedonlyafter24-48hr
e)Itprovide80%calorieneedofbody
CorrectAnswer-A:B:C:E
Ans.A,Itsupplies4kcalspergramB,Itincreasesinsulin
secretionC,Storedinliver&E,Itprovide80%calorieneedof
body
[Ref:Harper30th/176;Park23rd/613;LippincottBiochemistry
6th/329:Ganong25TH/24,24th/441;A.KIain5th/622-29]
Carbohydratemetabolism:
After12to18hoursoffasting,liverglycogenisalmosttotally
depleted.
Theliverservesasreceiving,manufacturing,storing&distributing
centreforglucose.
Liverglycogenisnearlyexhaustedafter10-18houroffasting.
Provides4k/calspergrams(protein-4;fat-9;dietaryfibre-2)
Themainsourceofenergyindietsiscarbohydratesare
carbohydratesderivedlargelyfromcereals.
Thesecerealsconstituteabout80%ofourdiet&provides50-80%
ofdailyenergyintake.
74.Nervevelocityisincreasedby:
a)Myelination
b)Smalleraxondiameter
c)Decreasedtemperature
d)Increaseinintracellularcalcium
e)Increaseinextracelluarsodium
CorrectAnswer-A
Ans.A.Myelination
[RefGanong25TH/94,24th/91;Guyton12th/72-7j;A.K'lain5th/147]
Greaterthediameterofagivennervefibre,thegreaterisitsspeed
(becausealargefiberofferslessresistancetohighcurrent.
Inmyelinatedfibres,thespeedofconductionisapproximately6
timesthefiberdiameter.
Thediameterofmyelinatedfibersrangefrom1-20micro/m,therifore
conductionvelocityvariesfrom6-120mts/sec
This post was last modified on 11 August 2021