BIOCHEMISTRY FINAL EXAM MULTIPLE CHOICE QUESTIONS WITH CORRECT ANSWERS 2025

BIOCHEMISTRY FINAL EXAM
MULTIPLE CHOICE QUESTIONS WITH
CORRECT ANSWERS 2025/2026
AminoAacidsAwithAnon-ionizableAsideAchainsAareAzwitterionsAwhenAtheyAare

a)AinAanyAsolution

b)inAsolutionsAwithApH>pKaAvalueAofAtheirAacidicAgroupAandApH<pKaAvalueAofAtheirAbasicAgroup

c)inAsolutionsAwithApH>pKaAvalueAofAtheirAacidicAgroupAandApH>pKaAvalueAofAtheirAbasicAgroup

d)AinAsolutionsAwithApH<pKaAvalueAofAtheirAacidicAgroupAandApH<pKaAvalueAofAtheirAbasicAgrou
p

e)inAsolutionsAwithApH<pKaAvalueAofAtheirAacidicAgroupAandApH>pKaAvalueAofAtheirAbasicAgroup
A-AcorrectAanswersb



AccordingAtoAtheAHenderson-
HasselbalchAequation,AwhenAtheAconcentrationsAofAprotonAacceptorAandAprotonAdonorAareAth
eAsame,AthenA

a)AtheAcarboxylicAacidAisAtotallyAneutralized

b)AonlyAsaltAformsAareApresent

c)ApHA=ApKa

d)ApKaA=AlogA[protonAacceptor/protonAdonor]

e)AtheApHAisAneutralA-AcorrectAanswersc

whatAinformationAcanAbeAgainedAbyAcomparingAtheAsequencesApfAproteinsAthatAhaveAtheAsame
AorAsimilarAfunctionAinAdifferentAspecies?



a)AtoAdetermineAevolutionaryArelationshipsAandArelatednessAofAspecies

b)AtoAdetermineAsequencesAthatAareAconservedAamongAspeciesAsinceAtheyAareAlikelyAtoAbeAimp
ortantAtoAtheAfunctionAandAstabilityAofAtheAproteins

c)AtoAlocateAhighlyAvariableAresiduesAwhichAcontributeAlittleAtoAtheAstructureAandAfunctionAofAt
heAprotein

d)AallAofAtheAabove

e)AnoneAofAtheAaboveA-AcorrectAanswersd

TheARAgroupAofAanAaminoAacidAdeterminesAifAitAis

a)AhydrophilicAorAhydrophobic

,b)ApolarAorAnonpolar

c)AchargedAorAuncharged

d)AanAacidAorAaAbase

e)AallAofAtheAaboveA-AcorrectAanswerse

WhatAisAtheAmajorAdrivingAforceAforAproteinAfolding?

a)AtheAhydrogenAbondsAthatAstabilizeAalphaAhelicesAandAbetaAsheets

b)AvanAderAwaalsAforces

c)AionicAforcesA(saltAbridges)

d)AcovalentAbonds,AlikeAdisulfideAbondsAbetweenAcysteineAresidues

e)AtheAincreaseAinAtheAentropyAofAtheAsolventAwhenAtheAproteinAfoldsA-AcorrectAanswerse

whichAstatementAexplainsAtheAcleaningAactionAofAsoapAonAgreasyAdishes?

a)AtheAsoapAchangesAtheAwater-
solubilityAofAtheAgreaseAsoAthatAitAisAeasilyAdissolvedAbyAtheAwater

b)AtheAsoapAhydratesAtheAgreaseAwithAitsApolarAheadAgroupsAandAholdsAitAinAsuspension

c)AtheAsoapAchemicallyAbreaksAdownAtheAgreaseAintoAsmaller,AmoreAwater-solubleAmolecules

d)AtheAgreaseAisAtrappedAinsideAtheAhydrophobicAinteriorAofAmicellesAmadeAofAsoapAmolecules

e)AtheAsoapAprotonatesAtheAgrease,AincreasingAitsApKa,AandAthusAtheAforwardArateAconstant,Ak1
,AforAdissolutionA-AcorrectAanswersd

HowAmanyAfragmentsAwillAresultAfromAtheAtreatmentAofAtrypsinAonAtheAfollowingAprotein?

Gly-Lys-Ala-Thr-Trp-Arg-Val-Ser-Tyr-Gln-Lys-Ile

a)A0

b)A1

c)A2

d)A3

e)A4A-AcorrectAanswerse

DisulfideAbridgesAcanAformAinAproteinsA_____________

a)AonlyAbetweenAcysteineAresiduesAside-by-sideAinAtheAproteinAsequence

b)AbetweenAcysteineAresiduesAthatAareAcloseAinA3DAspace,AbutAnotAnecessarilyAcloseAinAprimary
Astructure

, c)AbetweenA2AcysteineAresiduesAinAproteins

d)AbetweenAanyA2AmethioninesAorAcysteines

e)AonlyAinsideAtheAcellAwhereAitAisAaAreducingAenvironmentA-AcorrectAanswersb

DiluteAamountsAofAaceticAacidA(CH3COOH,ApKaA=A4.76)AareAmixedAinAbufferedAsolutionsAofApHA
=A2AandApHA=A7

a)AsinceAitAisAanAacid,AitAwillAbeAinAtheAacidicAform,AandAthusApositivelyAchargedAinAbothAsolution
s.

b)AitAwillAbeApresentApredominantlyAasAaApositivelyAchargedAspeciesAatApHA=A2

c)AitAwillAbeApresentApredominantlyAasAaAnegativelyAchargedAspeciesAatApHA=A2

d)AitAwillAbeApresentApredominantlyAasAaApositivelyAchargedAspeciesAatApHA=A7

e)AitAwillAbeApresentApredominantlyAasAaAnegativelyAchargedAspeciesAatApHA=A7A-
AcorrectAanswerse



YouAareAsequencingAaAproteinAsampleAviaAEdmanAdegradation,AandAafterAtheAfirstAroundAofAde
gradation,AyouAidentifyAaminoAacidsAderivatives.AWhichAofAtheAfollowingAareAreasonableAexpla
nationsAforAthisAresult?

a)AtheAsampleAisAimpureAandAcontainsAmultipleAdifferentAproteins

b)AtheAproteinAisAcomposedAofAseveralAdifferentAsubunits

c)AtheAproteinAisApartiallyAdegraded

d)AallAofAtheAabove

e)AnoneAofAtheAabove)A-AcorrectAanswersd

Alanine,Avaline,Aleucine,AandAisoleucineAareAimportantAinA3DAstructureAbecauseAthey

a)AareAbranched

b)AareAhighlyAhydrophobic

c)AareAhighlyAhydrophilic

d)AattractAwaterAmoleculesA-AcorrectAanswersb

WhichAwillAbeAdifferentAforAaAcatalyzedAreactionAversusAanAuncatalyzedAreaction?

a)AactivationAenergy

b)AgroundAstateAenergy

c)AfreeAenergyAchange