BIOCHEM - 1ST YEAR QUESTIONS AND CORRECT VERIFIED ANSWERS

BIOCHEM - 1ST YEAR QUESTIONS AND
CORRECT VERIFIED ANSWERS
AllA2aminoA2acidsA2containA2aA2centralA2carbon,A2aA2sideA2chainA2(RA2group),A2anA2aminoA
2groupA2andA2aA2__________A2group.A2-A2Ans--Carboxyl


AminoA2acidsA2canA2undergoA2aA2protonA2transfer,A2thusA2givingA2bothA2aA2(+)A2andA2(-)A2c
harge.A2ThisA2molecularA2stateA2isA2calledA2theA2________.A2-A2Ans--Zwitterion

AminoA2acidA2thatA2areA2unableA2toA2beA2synthesisedA2fromA2biochemicalA2pathwaysA2wit
hinA2aA2cellA2haveA2toA2beA2consumedA2throughA2dietaryA2intake.A2TheseA2areA2calledA2__
_____A2aminoA2acids.A2-A2Ans--Essential

WhenA2twoA2aminoA2acidsA2joinA2together,A2theyA2areA2joinedA2byA2anA2aideA2bond.A2ThisA
2isA2alsoA2referredA2toA2asA2aA2_______A2bond.A2-A2Ans--Peptide


WhichA2levelA2ofA2proteinA2structureA2involvesA2theA2aminoA2acidA2sequence,A2butA2notA2th
eA2foldingA2ofA2theA2protein?A2-A2Ans--Primary

UnfoldingA2aA2proteinA2usingA2heatA2isA2aA2processA2calledA2________.A2ThisA2processA2d
oesA2notA2affectA2theA2primaryA2sequenceA2ofA2theA2protein.A2-A2Ans--Denaturation

IfA2aA2neutralA2aminoA2acidA2isA2placedA2inA2aA2veryA2basicA2environmentA2(pHA2>A210),A2itA
2willA2loseA2aA2protonA2(H+)A2fromA2theA2__________A2functionalA2group.A2-A2Ans--
CarboxylA2-A2COOH

DisulphidesA2bondsA2areA2covalentA2bondsA2betweenA2twoA2_______A2aminoA2acids.A2-
A2Ans--Cysteine


TheA2processA2ofA2breakingA2theA2bondsA2betweenA2aminoA2acidsA2withinA2aA2polypeptide
A2isA2calledA2aA2______A2reaction.A2-A2Ans--Hydrolysis


AllA2aminoA2acidsA2containA2bothA2anA2acidicA2carboxylA2groupA2andA2aA2basicA2______A2
group.A2-A2Ans--Amino

AminoA2acidsA2neverA2existA2inA2natureA2asA2neutralA2molecules;A2ratherA2theyA2undergoA2
aA2protonA2transferA2toA2formA2aA2______.A2-A2Ans--Zwitterion

HumansA2areA2unableA2toA2produceA2_____A2ofA2theA2aminoA2acidsA2required,A2andA2ther
eforeA2theyA2areA2referredA2toA2asA2essentialA2aminoA2acids.A2-A2Ans--10

IfA2anA2aminoA2acidA2isA2placedA2inA2aA2veryA2acidicA2environmentA2(pHA2<A22)A2whichA2fun
ctionalA2groupA2gainsA2aA2protonA2(H)?A2-A2Ans--CarboxylA2group

, TheA2aminoA2acidA2atA2theA2"ends"A2ofA2theA2peptideA2canA2beA2eitherA2aA2N-
terminalA2aminoA2acidA2orA2aA2________A2aminoA2acid.A2-A2Ans--C-terminal

WhichA2levelA2ofA2proteinA2structureA2describesA2theA23DA2arrangementA2ofA2localisedA2re
gions?A2-A2Ans--SecondaryA2structure

EachA2turnA2inA2anA2alphaA2helixA2containsA2____A2(number)A2aminoA2acidA2residues.A2-
A2Ans--3.6


SomeA2enzymes,A2suchA2asA2pepsin,A2breakA2downA2polypeptidesA2byA2______.A2-
A2Ans--Hydrolysis


VariousA2processes,A2includingA2heating,A2canA2achieveA2disruptionA2ofA2secondary,A2terti
ary,A2andA2evenA2quaternaryA2proteinA2structure.A2ThisA2typeA2ofA2changeA2inA2aA2proteins
A2shapeA2isA2termedA2______A2.A2-A2Ans--Denaturation


ThereA2areA2_____A2aminoA2acidsA2thatA2humansA2mustA2obtainA2fromA2dietA2andA2can'tA2
produce.A2-A2Ans--10

AllA2aminoA2acidsA2containA2theA2acidicA2_____A2groupA2andA2aA2basicA2aminoA2groupA2-
A2Ans--Carboxyl


AminoA2acidsA2neverA2existA2inA2natureA2asA2neutralA2molecules;A2theyA2undergoA2aA2___
___A2transferA2toA2fromA2aA2zwitterion.A2-A2Ans--Proton

InA2theA2FischerA2projectionsA2whenA2LA2andA2DA2isomersA2canA2beA2identifiedA2byA2theA2p
ositionA2ofA2NH3+A2group,A2_____A2isomersA2areA2consideredA2commonA2naturallyA2occur
ringA2aminoA2acids.A2-A2Ans--LA2isomers

IfA2anA2aminoA2acidA2isA2placedA2inA2anA2environmentA2withA2pHA2aroundA26,A2theyA2willA2e
xistA2inA2theirA2______A2form.A2-A2Ans--Zwitterion

WhichA2structureA2ofA2proteinA2showsA2theA2sequenceA2ofA2aminoA2acidsA2thatA2formA2the
A2protein?A2-A2Ans--Primary


______A2bondsA2areA2covalentA2bondsA2thatA2helpA2stabiliseA2theA2tertiaryA2structureA2ofA2
protein.A2-A2Ans--Disulfide

TheA2firstA2stepA2inA2digestionA2ofA2proteinA2involvesA2someA2enzymesA2suchA2asA2pepsin
A2inA2aA2processA2calledA2______.A2-A2Ans--Hydrolysis


SomeA2enzymesA2requireA2anA2additionalA2moleculeA2toA2beA2presentA2inA2orderA2forA2the
A2reactionA2toA2takeA2place.A2ThisA2additionalA2moleculeA2isA2calledA2aA2________.A2-
A2Ans--Co-factor