PORTAGE LEARNING
BIOCHEMISTRY 210: MODULE 1
EXAM - THE AMAZING WORLD OF
BIOCHEMISTRY QUESTIONS AND
ANSWERS
What qxare qxthree qxways qxthat qxbiochemists qxstudy qxbiological qxorganisms? qx-
qxANSWERS--1. qxThe qxrelationship qxbetween qxstructure qxand qxfunction qxof
qxbiomolecules.
2. qxThe qxchemical qxreactions qxof qxorganisms qxand qxor qxmetabolism.
3. qxCommunication qxwith qxand qxamong qxorganisms.
What qxis qxthe qxdefinition qxof qxbiochemistry? qx- qxANSWERS--Biochemistry qxis
qxreferred qxto qxas qxthe qx'chemistry qxof qxlife' qxas qxit qxinvestigates qxhow qxthe
qxproperties qxof qxorganisms qxrelate qxto qxtheir qxmolecules.
What qxelements qxare qximportant qxto qxhuman qxlife? qx- qxANSWERS--Bulk
qxelements qxand qxtrace qxelements.
Bulk qxelements qxconsists qxof qxnon-metals qxand qxtrace qxelements qxconsist qxof
qxtransition qxmetals qxand qxmetals. qx
Trace qxelements qxare qximportant qxin qxsmall qxamounts.
What qxare qxconsidered qxbulk qxelements? qx- qxANSWERS--C, qxH, qxN, qxO, qxP, qxS,
qxCl, qxNa, qxK, qxCa.
What qxare qxconsidered qxtrace qxelements? qx- qxANSWERS--Mg, qxV, qxCr, qxMn, qxFe,
qxCo, qxNi, qxCu, qxZn, qxMo, qxW, qxSe, qxI.
What qxis qxanother qxname qxfor qxfirefly? qx- qxANSWERS--Lightning qxbug qxor qxglow
qxworm. qxFireflies qxare qxalso qxknown qxto qxbe qxbeetles.
What qxare qxthe qxdifferent qxbond qxshapes? qx- qxANSWERS--Linear, qxTrigonal
qxplanar, qxTrigonal qxpyramidal, qxTetrahedral, qxBent.
Linear qx- qxANSWERS--180 qxdegrees, qxsp qxhybridization. qx
A qxstraight-line qxarrangement qxof qxatoms.
Trigonal qxPlanar qx- qxANSWERS--120 qxdegrees, qxsp2 qxhybridization. qx
, A qxcentral qxatom qxwith qxthree qxbonded qxgroups qxin qxa qxflat, qxplanar qxstructure.
Trigonal qxPyramidal qx- qxANSWERS--107.5 qxdegrees, qxsp3 qxhybridization.
A qxtrigonal qxpyramidal qxshape qxoccurs qxwhen qxa qxcentral qxatom qxforms qxthree
qxbonds qxand qxhas qxone qxlone qxpair qxof qxelectrons.
Tetrahedral qx- qxANSWERS--109.5 qxdegrees, qxsp3 qxhybridization. qx
A qxcentral qxatom qxwith qxfour qxsingle qxbonds, qxforming qxa qx3D qxtetrahedron.
Bent qx- qxANSWERS--104.5 qxdegrees, qxsp3 qxhybridization. qx120 qxdegrees, qxsp2
qxhybridization. qx
Water: qxThe qxcentral qxatom qxhas qxfour qxelectron qxdomains qx(two qxbonded qxatoms
qx+ qxtwo qxlone qxpairs). qxThe qxincreased qxlone qxpair qxrepulsion qxfurther qxreduces
qxthe qxbond qxangle qxfrom qxthe qxideal qxtetrahedral qx(~109.5°) qxto qx~104.5°.
What qxis qxknown qxas qxthe qx"medium qxof qxlife"? qx- qxANSWERS--Water qxis qxknown
qxas qxthe qx"medium qxof qxlife" qxbecause qxit qxmakes qxup qx70% qxor qxmore qxof
qxliving qxthings. qxIn qxhumans, qxwater qxis qxknown qxto qxmake qxup qxa qxlarge qxportion
qxof qxblood.
Are qxtransition qxmetals qxcommonly qxfound qxin qxbiological qxorganisms? qx-
qxANSWERS--Yes, qxtransition qxmetals qxare qxcommonly qxfound qxin qxbiological
qxorganisms qxin qxtrace qxamounts qxor qxsmall qxquantities. qx
For qxexample, qxIron qx(Fe) qxis qxsignificant qxin qxthe qxtransport qxof qxoxygen. qxIron
qxis qxa qxmineral qxfound qxwithin qxthe qxprotein qxhemoglobin qxin qxred qxblood qxcells
qxand qxhelps qxoxygen qxto qxbe qxdistributed qxfrom qxthe qxlungs qxto qxother qxtissues
qxin qxthe qxbody.
Can qxwater qxcan qxmake qxup qx85% qx(by qxmass) qxof qxa qxliving qxorganism. qx-
qxANSWERS--Yes. qxSome qxplants qxare qx90% qxwater qxby qxmass.
Properties qxof qxH20 qx- qxANSWERS--Water qxis qxpolar qxas qxhydrogen qxunequally
qxshares qxelectrons qxwith qxoxygen. qxIt qxhas qxa qxbent qxshape qxdue qxto qxthe
qxrepulsion qxof qxelectrons.
Oxygen qxis qxmore qxelectronegative qxthan qxhydrogen qxwhich qxis qxwhy qxit qxis qxa
qxpolar qxmolecule.
Why qxare qxsmaller qxelements qxfavored? qx- qxANSWERS--They qxcan qxform qxstable
qxcovalent qxbonds.
How qxdo qxstrong qxbonds qxform? qx- qxANSWERS--Through qxsignificant qxoverlap qxof
qxatoms qxsuch qxas qxcarbon qxand qxhydrogen qxpermitting qxthem qxto qxshare
qxelectrons. qx
BIOCHEMISTRY 210: MODULE 1
EXAM - THE AMAZING WORLD OF
BIOCHEMISTRY QUESTIONS AND
ANSWERS
What qxare qxthree qxways qxthat qxbiochemists qxstudy qxbiological qxorganisms? qx-
qxANSWERS--1. qxThe qxrelationship qxbetween qxstructure qxand qxfunction qxof
qxbiomolecules.
2. qxThe qxchemical qxreactions qxof qxorganisms qxand qxor qxmetabolism.
3. qxCommunication qxwith qxand qxamong qxorganisms.
What qxis qxthe qxdefinition qxof qxbiochemistry? qx- qxANSWERS--Biochemistry qxis
qxreferred qxto qxas qxthe qx'chemistry qxof qxlife' qxas qxit qxinvestigates qxhow qxthe
qxproperties qxof qxorganisms qxrelate qxto qxtheir qxmolecules.
What qxelements qxare qximportant qxto qxhuman qxlife? qx- qxANSWERS--Bulk
qxelements qxand qxtrace qxelements.
Bulk qxelements qxconsists qxof qxnon-metals qxand qxtrace qxelements qxconsist qxof
qxtransition qxmetals qxand qxmetals. qx
Trace qxelements qxare qximportant qxin qxsmall qxamounts.
What qxare qxconsidered qxbulk qxelements? qx- qxANSWERS--C, qxH, qxN, qxO, qxP, qxS,
qxCl, qxNa, qxK, qxCa.
What qxare qxconsidered qxtrace qxelements? qx- qxANSWERS--Mg, qxV, qxCr, qxMn, qxFe,
qxCo, qxNi, qxCu, qxZn, qxMo, qxW, qxSe, qxI.
What qxis qxanother qxname qxfor qxfirefly? qx- qxANSWERS--Lightning qxbug qxor qxglow
qxworm. qxFireflies qxare qxalso qxknown qxto qxbe qxbeetles.
What qxare qxthe qxdifferent qxbond qxshapes? qx- qxANSWERS--Linear, qxTrigonal
qxplanar, qxTrigonal qxpyramidal, qxTetrahedral, qxBent.
Linear qx- qxANSWERS--180 qxdegrees, qxsp qxhybridization. qx
A qxstraight-line qxarrangement qxof qxatoms.
Trigonal qxPlanar qx- qxANSWERS--120 qxdegrees, qxsp2 qxhybridization. qx
, A qxcentral qxatom qxwith qxthree qxbonded qxgroups qxin qxa qxflat, qxplanar qxstructure.
Trigonal qxPyramidal qx- qxANSWERS--107.5 qxdegrees, qxsp3 qxhybridization.
A qxtrigonal qxpyramidal qxshape qxoccurs qxwhen qxa qxcentral qxatom qxforms qxthree
qxbonds qxand qxhas qxone qxlone qxpair qxof qxelectrons.
Tetrahedral qx- qxANSWERS--109.5 qxdegrees, qxsp3 qxhybridization. qx
A qxcentral qxatom qxwith qxfour qxsingle qxbonds, qxforming qxa qx3D qxtetrahedron.
Bent qx- qxANSWERS--104.5 qxdegrees, qxsp3 qxhybridization. qx120 qxdegrees, qxsp2
qxhybridization. qx
Water: qxThe qxcentral qxatom qxhas qxfour qxelectron qxdomains qx(two qxbonded qxatoms
qx+ qxtwo qxlone qxpairs). qxThe qxincreased qxlone qxpair qxrepulsion qxfurther qxreduces
qxthe qxbond qxangle qxfrom qxthe qxideal qxtetrahedral qx(~109.5°) qxto qx~104.5°.
What qxis qxknown qxas qxthe qx"medium qxof qxlife"? qx- qxANSWERS--Water qxis qxknown
qxas qxthe qx"medium qxof qxlife" qxbecause qxit qxmakes qxup qx70% qxor qxmore qxof
qxliving qxthings. qxIn qxhumans, qxwater qxis qxknown qxto qxmake qxup qxa qxlarge qxportion
qxof qxblood.
Are qxtransition qxmetals qxcommonly qxfound qxin qxbiological qxorganisms? qx-
qxANSWERS--Yes, qxtransition qxmetals qxare qxcommonly qxfound qxin qxbiological
qxorganisms qxin qxtrace qxamounts qxor qxsmall qxquantities. qx
For qxexample, qxIron qx(Fe) qxis qxsignificant qxin qxthe qxtransport qxof qxoxygen. qxIron
qxis qxa qxmineral qxfound qxwithin qxthe qxprotein qxhemoglobin qxin qxred qxblood qxcells
qxand qxhelps qxoxygen qxto qxbe qxdistributed qxfrom qxthe qxlungs qxto qxother qxtissues
qxin qxthe qxbody.
Can qxwater qxcan qxmake qxup qx85% qx(by qxmass) qxof qxa qxliving qxorganism. qx-
qxANSWERS--Yes. qxSome qxplants qxare qx90% qxwater qxby qxmass.
Properties qxof qxH20 qx- qxANSWERS--Water qxis qxpolar qxas qxhydrogen qxunequally
qxshares qxelectrons qxwith qxoxygen. qxIt qxhas qxa qxbent qxshape qxdue qxto qxthe
qxrepulsion qxof qxelectrons.
Oxygen qxis qxmore qxelectronegative qxthan qxhydrogen qxwhich qxis qxwhy qxit qxis qxa
qxpolar qxmolecule.
Why qxare qxsmaller qxelements qxfavored? qx- qxANSWERS--They qxcan qxform qxstable
qxcovalent qxbonds.
How qxdo qxstrong qxbonds qxform? qx- qxANSWERS--Through qxsignificant qxoverlap qxof
qxatoms qxsuch qxas qxcarbon qxand qxhydrogen qxpermitting qxthem qxto qxshare
qxelectrons. qx
