x
x
x
x
x
x
x
x
x
x
x
MEDICAL BIOCHEMISTRY EXAM 1
x x x
QUESTIONS AND ANSWERS
x x x
WELL ILLUSTRATED.
x x x
x
x
x
x
x
x
x
x
x
Describe xthe xphysical xand xchemical xproperties x of x water -
x x correct
xanswers.Abnormally x
x x
high xboiling xpoint x(100 xdegrees
xCelsius)
x
Abnormally xhigh xfreezing xpoint x(0 xdegrees
xCelsius)
x
Abnormally xhigh xmelting
xpoint
x
Solid xis xless xdense xthan xliquid x(ice xfloats xin xliquid
xwater)
x
Heat
xcapacity x
x
H
xbonding x
x x
Dipolar
xcharacter
x
Dissociation xinto xcharged
xparticles
x
Describe xthe xeffects xof xhydrogen xbonding xin xphysiological xsolutions x- xcorrect
xanswers.Rates xof xenzyme xreactions x
Permeabiliyy xof xmembranes xto xmany xmolecules
xStability xand xconformation xof xproteins, xetc. x x
Rates xof xtransport xthrough xmembranes x
Absorption, xetc. xof xdrugs x
Hydrophobicity xor xhydrophilicity xof xa xcompound x
x
, Explain xthe xHenderson-Hasselbach xequation x- xcorrect xanswers.pH x= xpKa x+ xlog
x([A-
x
]/[HA])
x
When xlog x= x0, xpH x= xpKa xand xamount xof xacid/base xis
xequal
x
Describe xthe xrole xof xbuffers xin xphysiology xand xchemistry x- xcorrect xanswers.Buffers
xmaintain xthe xpH, xto xallow xreactions xto xoccur xwithout xupsetting xthe xbalance xof xthe
xsystem. xPhosphate xand xbicarbonate: xbicarbonate xbuffer xsystem xis xmore ximportant
xbecause xthere x
is xmore xof xit x(carbonic xanhydrase xis ximportant xfor xthe xbody) x
Buffers xkeep xpH xwithin x1 xpH xunit x(either xside) x
x
Describe xthe xdifferences xin xmetabolic xand xrespiratory xacidosis xand xalkalosis x-
xcorrect xanswers.Metabolic xacidosis x- xusage xof x"fuels" xincrease xin xlactic xacid xin
xbody, xkidney xexcretes xsulfuric xacid, xlactic xacid, xammonia, xand xphosphoric xacid x
Respiratory xacidosis x- xcarbonic xacid xto xbe xexcreted xby xlungs, xtoo xmuch xCO2 xin
xbody xRespiratory xalkalosis x- xdecreased xin xmetabolism xof xfuels, xtoo xmuch xO2 xdue xto
xhyperventilation, xdecrease xpressure xof xCO2 x
x
Describe xthe xcategories xof xthe x20 xamino xacids xfound xin xproteins x-
xcorrect x
x x
answers.Simple
xAliphatic
x
Aliphatic xwith xhydroxyl xor xsulfur xside
xchains
x x
Aromatic
x
Basic
x
x
Acidic x with
xamides
x
Describe xproperties xof xthe xsimple xaliphatic xamino xacids x- xcorrect
xanswers.Hydrophobic xcharacter xincreases xwith xchain xsize. x xGlycine x- xprecursor xfor
xhemes xand xpurines x
Alanine x- xprecursor xfor xglucose xin xglyconeogensis x
Valine x
Isoleucine x
Leucine x
Proline x- xsecondary xamine, xconstraints xon xshape x
*Maple xsyrup xdisease x- xValine, xIsoleucine, xLeucine x
x
Describe xproperties xof xthe xaliphatic xamino xacids xcontaining xhydroxyl xgroups xor
xsulfur x-
correct xanswers.Hydroxyl x- xmodified xby xphosphorylation, xweakly xpolar xand
xhydrophilic x
x
x
x
x
x
x
x
x
x
x
MEDICAL BIOCHEMISTRY EXAM 1
x x x
QUESTIONS AND ANSWERS
x x x
WELL ILLUSTRATED.
x x x
x
x
x
x
x
x
x
x
x
Describe xthe xphysical xand xchemical xproperties x of x water -
x x correct
xanswers.Abnormally x
x x
high xboiling xpoint x(100 xdegrees
xCelsius)
x
Abnormally xhigh xfreezing xpoint x(0 xdegrees
xCelsius)
x
Abnormally xhigh xmelting
xpoint
x
Solid xis xless xdense xthan xliquid x(ice xfloats xin xliquid
xwater)
x
Heat
xcapacity x
x
H
xbonding x
x x
Dipolar
xcharacter
x
Dissociation xinto xcharged
xparticles
x
Describe xthe xeffects xof xhydrogen xbonding xin xphysiological xsolutions x- xcorrect
xanswers.Rates xof xenzyme xreactions x
Permeabiliyy xof xmembranes xto xmany xmolecules
xStability xand xconformation xof xproteins, xetc. x x
Rates xof xtransport xthrough xmembranes x
Absorption, xetc. xof xdrugs x
Hydrophobicity xor xhydrophilicity xof xa xcompound x
x
, Explain xthe xHenderson-Hasselbach xequation x- xcorrect xanswers.pH x= xpKa x+ xlog
x([A-
x
]/[HA])
x
When xlog x= x0, xpH x= xpKa xand xamount xof xacid/base xis
xequal
x
Describe xthe xrole xof xbuffers xin xphysiology xand xchemistry x- xcorrect xanswers.Buffers
xmaintain xthe xpH, xto xallow xreactions xto xoccur xwithout xupsetting xthe xbalance xof xthe
xsystem. xPhosphate xand xbicarbonate: xbicarbonate xbuffer xsystem xis xmore ximportant
xbecause xthere x
is xmore xof xit x(carbonic xanhydrase xis ximportant xfor xthe xbody) x
Buffers xkeep xpH xwithin x1 xpH xunit x(either xside) x
x
Describe xthe xdifferences xin xmetabolic xand xrespiratory xacidosis xand xalkalosis x-
xcorrect xanswers.Metabolic xacidosis x- xusage xof x"fuels" xincrease xin xlactic xacid xin
xbody, xkidney xexcretes xsulfuric xacid, xlactic xacid, xammonia, xand xphosphoric xacid x
Respiratory xacidosis x- xcarbonic xacid xto xbe xexcreted xby xlungs, xtoo xmuch xCO2 xin
xbody xRespiratory xalkalosis x- xdecreased xin xmetabolism xof xfuels, xtoo xmuch xO2 xdue xto
xhyperventilation, xdecrease xpressure xof xCO2 x
x
Describe xthe xcategories xof xthe x20 xamino xacids xfound xin xproteins x-
xcorrect x
x x
answers.Simple
xAliphatic
x
Aliphatic xwith xhydroxyl xor xsulfur xside
xchains
x x
Aromatic
x
Basic
x
x
Acidic x with
xamides
x
Describe xproperties xof xthe xsimple xaliphatic xamino xacids x- xcorrect
xanswers.Hydrophobic xcharacter xincreases xwith xchain xsize. x xGlycine x- xprecursor xfor
xhemes xand xpurines x
Alanine x- xprecursor xfor xglucose xin xglyconeogensis x
Valine x
Isoleucine x
Leucine x
Proline x- xsecondary xamine, xconstraints xon xshape x
*Maple xsyrup xdisease x- xValine, xIsoleucine, xLeucine x
x
Describe xproperties xof xthe xaliphatic xamino xacids xcontaining xhydroxyl xgroups xor
xsulfur x-
correct xanswers.Hydroxyl x- xmodified xby xphosphorylation, xweakly xpolar xand
xhydrophilic x
