MCQs in Biochemistry

Biochemistry  Basic Medical Science Time: 40 mins

Author Email: [email protected] Total Marks: 50 | Pass Marks: 30

BIOCHEMISTRY Pleaseuseadarkpencil/pentocompl Pleaseuseadarkpencil/pentocompletethetest.Readtheinstruc etethetest.Readtheinstructionsatthe tionsatthe beginingcarefully.ThisisanSample beginingcarefully.ThisisanSampleTestPaperforpractice. TestPaperforpractice. PleaseNote:ThereisaNegativeMarkingof(-1)foreachincorrectresponse. 1. Infatt Infattyacids yacidsynthe ynthesis,t sis,theenz heenzym ymerequ erequiredfo iredforpr rprimingac imingacetyl-ACPwith etyl-ACPwith malonyl-ACPforchainextension  A 3-ketoacyl-ACPreductase

 AcetylCoA: CoA:ACPt ACPtran ransac sacylas ylase e C  Acetyl

B 3-ketoacyl-ACPsynthase

D MalonylCoA:ACPtransacylase

2. Anenzyme Anenzymeoft ofthenon henon-oxidat -oxidativephas ivephaseof eofthe thepentos pentosephos ephosphate phatepath pathway: way:  A Ribulose5-Phosphate 3-Epimerase

C Methylcrotonyl-CoAcarboxylase

B 6-phosphogluconate dehydrogenase

 Acetyl-CoA CoAcar carbox boxylas ylasea ealpha lpha D  Acetyl-

3. Biotindeficiencyisch Biotindeficiencyischaract aracterizedb erizedbyallof yallofthef thefollowingexcept ollowingexcept::  A hypercholesterolemia

C scalydermatitis

B glossitis

D dementia

4. Matcht Matchthefo hefollowingVitaminswith llowingVitaminswiththeir theirdailyreco dailyrecomm mmended endeddietary dietaryintake intakeas as supplement:  A.

Thiamine Thiamine

A. 5mg 5mg

B.

Cobalamin (Vit.B12)

B. 1. 1.1-1.2 mg

C.

Niacin

C. 14-16 mg

D.

Pantothenic acid (B5)

D. 2.4 mg

E.

Biotin

E. 30 μg

5. Caroten Carotenoids oidswitho without utVitam VitaminA inAact activity ivity::  A γ-carotene

C zeaxanthin

B β-cryptoxanthin

D lycopene

Basic Medical Sciences

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Biochemistry  6. Theenzym Theenzymetha ethatca tcatalyzes talyzesredu reductivea ctiveaminat minationof ionofα-k α-ketoglut etoglutarat arateinpro einprokaryo karyotes tes andplants  A glutamatesynthase

C glutamatedehydrogenase

B glutaminase

D glutaminesynthetase

7. Arrangethe Arrangethefollowingsub followingsubstra strates tesoft oftheglyco heglycolyticpat lyticpathwayint hwayintheircor heircorrect rectorde orderof rof even events ts//reac reacti tion ons: s:( (1 1 5)  A.

1,3-Bisp 1,3-Bisphos hospho phoglyc glycera erate te

B.

Fructose 1,6-bisp isphosphate

C.

Phosphoenolpyruvate

D.

Glyc lyceralde ldehyde 3-phosphate

E.

Glucose 6-phosphate

8. Hyperke Hyperkerat ratosis osisca cano noccu ccurd rdue ueto to  A Vemurafenib

C chronicexposuretoMercury

B chronicexposuretoArsenic

D alloftheabove

9. Whatisno Whatisnottr ttrueabo ueaboutho utholoenzym loenzymes? es?  A DNApolymerasesareexamples ofholoenzyme

C cofactorsinholoenzymesare mostlyenzymesorproteins

B containscofactorsweaklybound toenzymescalledprosthetic groups

D apoenzyme+coenzyme

10. Matcht Matchthefo hefollowingenzym llowingenzymewitht ewiththeirinorga heirinorganiccof niccofacto actors: rs:  A.

catalase catalase

A. manga manganes nese e

B.

cytochrome

B. ma magnesium

C.

hexokinase

C. mo molybdenum

D.

arginase

D. fe ferrous or ferric

E.

nitrate reductase

E. cupric

11. Anexampleof Anexampleofoxidored oxidoreductas uctaseenz eenzyme yme  A chymotrypsin

C lactatedehydrogenase

B fumarase

D aminoacyl-tRNAsynthetase

12. Thepyruvat Thepyruvatedehy edehydrogen drogenasem asemultienzym ultienzymecom ecomplexre plexrequireallof quireallofthef thefollowing ollowing cofactorsexcept:  A thiaminepyrophosphate(TPP)

C favinadeninedinucleotide(FAD)

B cobalt

D magnesium

Basic Medical Sciences

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Biochemistry  13. Theenzym Theenzymetha ethatco tconvert nvertsgluta sglutaminet minetoglutam oglutamate ateandNH andNH4+inlivermitochondria  A glutaminesynthetase

C glutamatedehydrogenase

B glutamatesynthase

D glutaminase

14. Serineis Serineissyn synthe thesize sizedf dfrom rom::  A glutamate

C α-ketoglutarate

B 3-phosphoglycerate

D 3-phosphohydroxypyruvate

15. Aminoacidthre Aminoacidthreonineissy onineissynthes nthesizedfr izedfrom om  A 3-phosphoglycerate

C aspartate

B pyruvate

D glutamine

16. Whichoft Whichofthefo hefollowingsubsta llowingsubstances ncesis/are is/arerespo responsiblefor nsibleforbraine brainedema demaduet dueto o astrocyteswellinginhepaticencephalopathy?  A glutamine

C glutamate

B ammonia

D alloftheabove

17. Matcht Matchthefo hefollowingenzym llowingenzymeswith eswiththeirc theircorrec orrectclass tclassificationsu ificationsubgrou bgroup: p:  A.

phosph phospholipas olipaseC eC

A. Hydrolas Hydrolase e

B.

lactate dehydrogenase

B. Transferases

C.

phosphoglucomutase

C. Oxidoreductase

D.

fumarase

D. Isomerase

E.

UDP-gluc lucose pyrophosphorylas lase E. Lyases

18. Formationof Formationofglutam glutamineiscat ineiscatalyzedb alyzedby y  A glutaminesynthetase

C glutamatesynthase

B glutaminase

D glutamatedehydrogenase

19. Whichoft Whichofthefo hefollowingisanendo llowingisanendogenous genousNMDAr NMDArecept eceptoran orantagon tagonist? ist?  A dextromethorphan

C kainicacid

B kynurenicacid

D glutamicacid

20. Whichoft Whichofthefo hefollowingenzym llowingenzymeisalyas eisalyase? e?  A glutaminesynthetase

C aspartatetranscarbamylase

B histidinedecarboxylase

D Uracil-DNAglycosylase

Basic Medical Sciences

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Biochemistry  21. Whichoft Whichofthefo hefollowingisnott llowingisnottruea rueabout boutVitam VitaminE? inE?  A regulationofprostaglandin synthesis

C protectsintegrityofnormalcell membranes

B largedosesmayinduceVitamin  Adeficie  Adeficiency ncy

D largedosesmayinduce hemolysisofRBC

22. Whichoft Whichofthefo hefollowingisaxant llowingisaxanthophyllcar hophyllcaroteno otenoids? ids?  A β-carotene

C lutein

B lycopene

D β-cryptoxanthin

23. Whichvitam Whichvitaminisneces inisnecessary saryfor formet metabolicoxidat abolicoxidationoft ionoftyrosine? yrosine?  A VitaminC

C Pyridoxine

B VitaminE

D Biotin

24. Anesse Anessent ntialam ialaminoa inoacid cid  A proline

C tryptophan

B alanine

D tyrosine

25. Whichoft Whichofthefo hefollowingisacof llowingisacofactor actorofM ofMethy ethylmalonylCoen lmalonylCoenzym zymeAm eAmutas utase(M e(MUT)? UT)?  A methylcobalamin

C cyanocobalamin

B adenosylcobalamin

D hydroxocobalamin

26. Vitaminthatis Vitaminthatisessent essentialforf ialforform ormationof ationofcollagen collagen  A Pyridoxine

C VitaminE

B VitaminD

D VitaminC

27. Hormone Hormonest sthat hatac actt tthro hrough ughCa Ca2+andphosphatidylinositolbisphosphate(PIP) system  A oxytocin

C glucagon

B atrialnatriureticpeptide(ANP)

D insulin

28. Enzymetha Enzymethatcat tcatalyzes alyzesthes thesynth ynthesisof esisoffum fumarat aratefr efrom omsuccinat succinateand eandFAD FAD  A succinyldehydrogenase

C succinylCoAsynthetase

B α-ketoglutaratedehydrogenase

D succinatedehydrogenase

29. SuccinylCoAisa[A]_ SuccinylCoAisa[A]________ ____________ _____com compound. pound.  ∆G°forhydrolysisofATPis[B]__________________.

Basic Medical Sciences

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Biochemistry  30. Whichoft Whichofthefo hefollowingsubstr llowingsubstrateinhibits ateinhibitscarn carnitineacyt itineacytransf ransferase eraseI? I?  A acetylCoA

C palmitoylCoA

B malonylCoA

D succinylCoA

31. Picktheincorr Picktheincorrect ectstat stateme ements ntsabout aboutthe thetricar tricarboxylicac boxylicacidcycle( idcycle(TCAcycle) TCAcycle)  A involvesoxidationofacetylCoA

C requireenzymesuccinate dehydrogenasewhichisa mitochondrialmatrixenzyme

B amphiboliccyclewhichprovides carbonskeletonfor gluconeogenesis,fattyacid synthesis

D pathwayforreductionand reoxidationofcoenzymes

32. Formationof Formationofm methylm ethylmalonylCoAf alonylCoAfrom rompropiony propionylCoArequire lCoArequirewhichvita whichvitaminas minasa a cofactor?  A Thiamine

C VitaminB12

B Pyridoxine

D VitaminB7

33. Schardin Schardinger geren enzym zymeis eisfo found undin in  A cheese

C boiledmilk

B yoghurt

D rawmilk

34. Whichvitam Whichvitaminisrequ inisrequiredas iredasapre aprecurso cursorint rinthebiosyn hebiosynthes thesisofc isofcoenzy oenzyme meA(CoA)? A(CoA)?  A Panthotheticacid

C Pyridoxine

B Folicacid

D Biotin

35. Constituents Constituentsofen ofenzym zymexant exanthineoxidas hineoxidase: e:  A riboflavin

C molybdenum

B ironatoms

D alloftheabove

36. Matcht Matchthefo hefollowingcofact llowingcofactorswith orswiththeir theirsourc sources: es:  A.

Nicotinam Nicotinamider ideringo ingofN fNAD AD+

B.

Flav lavin adenine ine dinucleo leotide ide FAD B. Niacin

C.

Coenzyme A (CoA)

C. Thiamine

D.

α-ketoacid dehydrogenases

D. Pantothenic acid

Basic Medical Sciences

 A. Riboflavin Riboflavin

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Biochemistry  37. Regardingα-s Regardingα-subunits ubunitsofvo ofvoltagega ltagegateds tedsodium odiumchanne channels(Nav) ls(Nav)tru trueis: eis:  A fourrepeatdomainswithsix membrane-spanningsegments

C poreconsistingselectivityfilter madeofpositivelychargesamino acids

B sixrepeatdomainswithfour membrane-spanningsegments

D α-subunitNav1.3expressedin dorsalrootgangliaisassociated withpain

38. Whatisno Whatisnottr ttrueabo ueaboutpy utpyruvat ruvatekinase? ekinase? C cofactorofpyruvatekinaseisK+

 A catalyzesthelastreactionin glycolysis

D isthekeyenzymeofglycolysisin muscles

B ismoreactiveinfastingstate

39. Whichoft Whichofthefo hefollowingenzym llowingenzymesre esrequirelipoicacidf quirelipoicacidforits oritsactivity activity? ?  A pyruvatedehydrogenase

C α-ketoaciddehydrogenase

B indole2,3,dioxygenase

D superoxidedismutase

40. Whichoft Whichofthefo hefollowingenzym llowingenzymeisan eisanoxidase oxidase/oxidor /oxidoreduct eductase? ase?  A glutamatedecarboxylase

C  2-furoyl-CoA dehydrogenase 2-furoyl-CoAdehydrogenase

B tyrosinase

D uridinemonophosphate synthetase

41. Thegenetha Thegenethatco tcodesf desforen orenzym zymeUridinem eUridinemonophos onophosphate phatesynth synthetas etaseislocat eislocatedon edon the  A shortarmofchromosome3(3p13) B shortarmofchromosome11(3 p11)

C longarmofchromosome11 (3q11) D longarmofchromosome3(3q13)

42. Conversionofβ Conversionofβ-car -carotene oteneintoVitam intoVitaminAoccu inAoccursch rschieflyinth ieflyinthe e  A brain

C intestine

B kidney

D liver

43. Pellagrais Pellagraisdue duet tod odefic eficienc iencyo yof f   A Niacin

C Thiamine

B Riboflavin

D Biotin

44. Wildtypest Wildtypestrainof rainofbact bacteriath eriathatdo atdonot notrequire requireany anygrowth growthfac factors tors::  A Lactobacillus

C Haemophilusinfluenzae

B E.coli

D Neisseriameningitidis

Basic Medical Sciences

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Biochemistry  45. Synthesisof SynthesisofPorphy Porphyrinringr rinringrequires equiresallofth allofthefollowingex efollowingexcept: cept:  A acetylCoA

C succinylCoA

B glycine

D δ-Aminolevulinicacid

46. Amnesicshellfishp Amnesicshellfishpoisoningisdu oisoningisdueto etoneurot neurotoxin oxin  A β-N-methylamino-l-alanine

C domoicacid

B okadaicacid

D conotoxin

47. Whichoft Whichofthefo hefollowingisinvolvedingr llowingisinvolvedingrowtha owthanddiff nddifferent erentiation? iation?  A Retinoicacid

C Retinol

B Retinal

D Retinene

48. Whatisno Whatisnottr ttruere ueregardingc gardingcongenita ongenitaleryth lerythropoiet ropoieticporph icporphyria? yria?  A urineofpatientsappearred

C deficiencyofcosynthase

B increasedsynthesisof δ-aminolevulinate

D formationoflargeamountof uroporphyrinogenI

49. Themainsto Themainstorage rageform formofv ofvitam itaminKinanim inKinanimals: als:  A VitaminK2

C phylloquinone

B VitaminK1

D phytomenadione

50. Avidinbindstowhichv Avidinbindstowhichvitamin itaminandinduc andinducesits esitsdeficiency deficiency? ?  A VitaminB6

C VitaminB12

B VitaminB1

D VitaminB7

Basic Medical Sciences

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