Name___________________________________ Exam MULTIPLECHOICE.Choosetheonealternativethatbestcompletesthestatementoranswersthequestion. 1
Which functiona lgroupis not presentin this molecule ?
1)
_____
sulfhydryl
B)
hydroxyl
C)
carboxyl
D)
amino
The extracellu larmatrix isthought to participat einthe regulatio nof animal cell behavior by communi cating informati onfrom the outsideto theinside ofthecell viawhich ofthe following ?
2)
_____
DNAandRNA
plasmodesmata
thenucleus
gapjunctions
integrins
A covalent chemical bondis onein which
3)
_____
outer-shell electronsofone atomare transferredtothe innerelectron shellsofanother atom.
protonsand neutronsare sharedbytwo atomssoasto satisfythe requirementsof bothatoms.
electronsare removedfromone atomand transferredto anotheratomso thatthetwoatoms becomeoppositely charged.
theinner-shell electronsofone atomare transferredtothe outershellof anotheratom.
outer-shell electronsoftwo atomsareshared soasto satisfactorilyfill theouterelectron shellsofboth atoms.
What givesrise tothe cohesiven essof water molecule s?
4)
_____
nonpolarcovalent bonds
hydrophobic interactions
hydrogenbonds
ionicbonds
bothAandC
Whichof the following isan example of potential rather than kinetic energy?
5)
_____
waterrushingover NiagaraFalls
afireflyusing lightflashesto attractamate
aninsectforaging forfood
afoodmolecule madeupof energy-rich macromolecules
aboymowing grass Usethe information extractedfromthe periodictablein Figure2.2to answerthe following questions.
Figure2.2
How many electrons does nitrogen havein its valence shell?
6)
_____
7
B)
14
C)
8
D)
5
E)
2
Whatisa triacylgly cerol?
7)
_____
aproteinwith tertiarystructure
amoleculeformed fromthree alcoholsby dehydration reactions
alipidmadewith threefattyacids andglycerol
acarbohydrate withthreesugars joinedtogetherby glycosidic linkages
alipidthatmakes upmuchofthe plasmamembrane
Humans candigest starchbut not cellulose because
8)
_____
humanshave enzymesthatcan hydrolyzethebeta ()glycosidic linkagesofstarch butnotthealpha ()glycosidic linkagesof cellulose.
themonomerof starchisglucose, whilethe monomerof celluloseis galactose.
themonomerof starchisglucose, whilethe monomerof celluloseis maltose.
humansharbor starch-digesting bacteriainthe digestivetract.
humanshave enzymesthatcan hydrolyzethe alpha() glycosidic linkagesofstarch butnotthebeta ()glycosidic linkagesof cellulose.
Whichof the following statement sis(are) true about enzymecatalyzed reactions ?
9)
_____
Thefreeenergy changeofthe reactionis oppositefromthe reactioninthe absenceofthe enzyme.
Thereaction alwaysgoesinthe directiontoward chemical equilibrium.
Thereactionis fasterthanthe samereactionin theabsenceofthe enzyme.
AandBonly
A,B,andC
The tertiary structure ofa proteinis the
10)
_____
overallprotein structureresulting fromthe aggregationoftwo ormore polypeptide subunits.
orderinwhich aminoacidsare joinedina polypeptidechain.
uniquethreedimensionalshape ofthefullyfolded polypeptide.
organizationofa polypeptidechain intoanhelixor pleatedsheet.
bondingtogether ofseveral polypeptidechains byweakbonds.
How many molecule sof glycerol (C H O 383 )would be presentin 1Lofa1 M glycerol solution?
11)
_____
1
7 110
14
23 6.0210
92
Whatis the structural feature that allows DNAto replicate?
12)
_____
thepresenceof deoxyribose sugar
thepurine pyrimidine backbone
twistingofthe moleculetoform anhelix
complementary pairingofthe nitrogenousbases
thephospho diesterbonds
Whichof the following statement sabout the cytoskelet onis true?
13)
_____
Microfilaments arestructurally rigidandresist compression, while microtubules resisttension (stretching).
Thedynamic aspectof cytoskeletal functionismade possiblebythe assemblyand disassemblyofa largenumberof complexproteins intolarger aggregates.
Movementofcilia andflagellaisthe resultofmotor proteinscausing microtubulesto moverelativeto eachother.
Transportvesicles amongthe membranesofthe endomembrane systemproduce thecytoskeleton.
Chemicalsthat blockthe assemblyofthe cytoskeleton wouldcauselittle effectonthecell's metabolism
Whichof the following results froma transfer of electron(s )between atoms?
14)
_____
ionicbond
hydrogenbond
polarcovalent bond
hydrophobic interaction
nonpolarcovalent bond
Maltose, asugar foundin barley,is compose dofone glucose molecule joinedby a glycosidi clinkage to another glucose molecule. Howis maltose classified ?
15)
_____
asadisaccharide
B)
asahexose
asanucleotide
D)
asaglycogen
Whichof the following propertie sor processes dowe associate with living things?
16)
_____
evolutionary adaptations
respondingtothe environment
energyprocessing
growthand reproduction
alloftheabove
IfthepH ofa solution is changed frompH 5topH7, itmeans thatthe
17)
_____
concentrationof + H istwice(2X) whatitwasatpH 5.
concentrationof + H is100times greaterandthe concentrationof OH isonehundredthwhat theywereatpH5.
concentrationof + H ishalf(1/2) whatitwasatpH 5.
concentrationof OH isonehundredth(0.01X) whatitwasatpH 5.
concentrationof OH is100times greaterthanwhat itwasatpH5.
Ifa modern electron microsco pe(TEM) can resolve biological imagesto the nanomete rlevel,as opposed tothe bestlight microsco pe,thisis dueto whichof the following ?
18)
_____
Theelectron microscopehas muchgreaterratio ofimagesizeto realsize.
Theelectron microscopecannot imagewholecells atonetime.
Contrastis enhancedby stainingwith atomsofheavy metal.
Thefocallength oftheelectron microscopeis significantly longer.
Electronbeams havemuchshorter wavelengthsthan visiblelight.
Whatis the chemical mechanis mby which cells make polymers from monomer s?
19)
_____
hydrolysis
dehydration reactions
ionicbondingof monomers
theformationof disulfidebridges between monomers
phosphodiester linkages
TaySachs diseaseis ahuman genetic abnormal itythat resultsin cells accumula tingand becoming clogged withvery largeand complex lipids. Which cellular organelle mustbe involved inthis condition ?
20)
_____
theendoplasmic reticulum
membrane-bound ribosomes
thelysosome
mitochondria
theGolgi apparatus
The reactivity ofan atom arises from
21)
_____
thepotential energyofthe valenceshell.
theaverage distanceofthe outermostelectron shellfromthe nucleus.
thesumofthe potentialenergies ofalltheelectron shells.
theenergy difference betweenthesand porbitals.
theexistenceof unpairedelectrons inthevalence shell.
Which structurefunction pairis mismatch ed?
22)
_____
Golgi;protein trafficking
microtubule; muscle contraction
nucleolus; productionof ribosomal subunits
ribosome;protein synthesis
lysosome; intracellular digestion
A compoun d contains hydroxyl groupsas its predomin ant functiona lgroup. Whichof the following statement sistrue concernin gthis compoun d?
23)
_____
Itshoulddissolve inanonpolar solvent.
Itwon'tform hydrogenbonds withwater.
Itshoulddissolve inwater.
Itlacksan asymmetric carbon,anditis probablyafator lipid.
Itishydrophobic.
A covalent bondis likelyto bepolar when
24)
_____
thetwoatoms sharingelectrons areequally electronegative.
itisbetweentwo atomsthatare bothverystrong electronacceptors.
thetwoatoms sharingelectrons areofthesame element.
oneoftheatoms sharingelectrons ismuchmore electronegative thantheother atom.
thetwoatoms sharingelectrons aredifferent elements.
Allofthe following contain amino acids except
25)
_____
insulin.
hemoglobin.
antibodies.
enzymes.
cholesterol.
About25 ofthe92 natural elements are knownto be essential tolife. Which fourof these25 elements makeup approxim ately96% ofliving matter?
26)
_____
carbon,oxygen, phosphorus, sulfur,calcium
carbon,sulfur, hydrogen
carbon,sodium, chlorine,nitrogen
carbon,hydrogen, nitrogen,oxygen
oxygen,hydrogen, calcium,sodium
Many mammals control their body temperatu reby sweating. Which property ofwater ismost directly responsib leforthe abilityof sweatto lower body temperatu re?
27)
_____
water'sabilityto dissolvemolecules intheair
water'shigh surfacetension
theabsorptionof heatbythe breakingof hydrogenbonds
water'schangein densitywhenit condenses
thereleaseofheat bytheformation ofhydrogenbonds
TheR groupor sidechain ofthe amino acid serineis CH OH 2 .TheR groupor sidechain ofthe amino acid alanineis CH . 3 Where would you expectto findthese amino acidsina globular proteinin aqueous solution?
28)
_____
Bothserineand alaninewouldbe intheinteriorof theglobular protein.
Alaninewouldbe intheinterior,and serinewouldbe ontheexteriorof theglobular protein.
Serinewouldbe intheinterior,and alaninewouldbe ontheexteriorof theglobular protein.
Bothserineand alaninewouldbe intheinteriorand ontheexteriorof theglobular protein.
Bothserineand alaninewouldbe ontheexteriorof theglobular protein.
Forliving organism s,which ofthe following isan important conseque nceofthe firstlaw of thermody namics?
29)
_____
Organismsare unableto transformenergy.
Lifedoesnotobey thefirstlawof thermodynamics.
Theenergy contentofan organismis constant.
Theorganism ultimatelymust obtainallofthe necessaryenergy forlifefromits environment.
Theentropyofan organism decreaseswith timeasthe organismgrowsin complexity.
Reactants capable of interactin gtoform products ina chemical reaction mustfirst overcome a thermody namic barrier knownas the reaction's
30)
_____
entropy.
caloriccontent
endothermiclevel.
activationenergy.
free-energy content.
Whyare hydrocar bons insoluble inwater?
31)
_____
Themajorityof theirbondsare nonpolarcovalent carbon-tohydrogen linkages.
Theyareless densethanwater.
Theyexhibit considerable molecular complexityand diversity.
Theyare hydrophilic.
Themajorityof theirbondsare ionic
Whichof the following istrue regarding saturated fatty acids?
32)
_____
Theyareusually liquidatroom temperature.
Theyarethe predominantfatty acidincornoil.
Theyareusually producedby plants.
Theyhavedouble bondsbetween carbonatomsof thefattyacids.
Theyarethe principal moleculesinlard andbutter.
Figure3.2
How many gramsof the molecule inFigure 3.2would beequal to1mol ofthe molecule ? (Carbon =12, Oxygen= 16, Hydrogen =1)
33)
_____
29
B)
342
C)
60
D)
30
E)
150
Figure4.2
Shown herein Figure 4.2are the structures of glucose and fructose. These two molecule sare
34)
_____
structuralisomers.
enantiomers.
geometric isotopes.
geometric isomers.
nonisotopic isomers.
The differenc esamong thethree categorie sof cytoskele tal elements would suggest thateach ofthe following has specialize droles. Whichof the following isa correct match?
35)
_____
microtubulesand chromosome movement
microfilaments andciliarymotion
microtubulesand cleavagefurrow formation
intermediate filamentsand cytoplasmic streaming
microfilaments andthenuclear lamina
Amino acidsare acids because they always possess which functiona lgroup?
36)
_____
sulfhydryl
B)
amino
C)
aldehyde
D)
carbonyl
E)
carboxyl
Theliver is involved in detoxifica tionof many poisons and drugs. Whichof the following structures is primarily involved inthis process and therefore abundant inliver cells?
37)
_____
smoothER
Golgiapparatus
Nuclearenvelope
roughER
Transportvesicles
Testoster oneand estradiol aremale and female sex hormones , respectiv ely,in many vertebrate s.Inwhat way(s)do these molecule sdiffer fromeach other?
38)
_____
Testosteroneand estradiolare geometricisomers buthavethesame molecular formula.
Testosteroneand estradiolare enantiomersofthe sameorganic molecule.
Testosteroneand estradiolhave completely differentchemical structures.
Testosteroneand estradiolhave different functionalgroups attachedtothe samecarbon skeleton.
Testosteroneand estradiolare structuralisomers buthavethesame molecular formula.
Increasin gthe substrate concentra tioninan enzymati creaction could overcome whichof the following ?
39)
_____
allosteric inhibition
negativeenergyof activation
saturationofthe enzymeactivity
competitive inhibition
denaturizationof theenzyme
Whyis ATPan important molecule in metabolis m?
40)
_____
Itprovidesenergy couplingbetween exergonicand endergonic reactions.
Itshydrolysis providesaninput offreeenergyfor exergonic reactions.
Itsterminal phosphategroup containsastrong covalentbondthat whenhydrolyzed releasesfree energy.
Itsterminal phosphatebond haslessenergy thantheothertwo.
A,B,C,andD
Whichof the following statement sis represent ativeof the second lawof thermody namics?
41)
_____
Conversionof energyfromone formtoanotheris always accompaniedby somegainoffree energy.
Cellsrequirea constantinputof energytomaintain theirhighlevelof organization.
Withoutaninput ofenergy, organismswould tendtoward decreasing entropy.
Everyenergy transformationby acelldecreases theentropyofthe universe.
Heatrepresentsa formofenergy thatcanbeused bymostorganisms todowork.
Each element isunique and different from other elements because ofthe number of protonsin thenuclei ofits atoms. Whichof the following indicates the number of protonsin anatom's nucleus?
42)
_____
atomicweight
massnumber
atomicnumber
molecularweight
atomicmass
A chemical reaction thathasa positive Gis correctly described as
43)
_____
enthalpic.
spontaneous.
pathetic
endergonic.
exergonic
Some bacteria are metabolic ally activein hot springs because
44)
_____
theirenzymesare completely insensitiveto temperature.
theyareableto maintainacooler internal temperature.
theyuse moleculesother thanproteinsor RNAsastheir maincatalysts.
hightemperatures makecatalysis unnecessary.
theirenzymes havehighoptimal temperatures.
Whichof the following isamajor causeof thesize limitsfor certain typesof cells?
45)
_____
theneedfora surfaceareaof sufficientareato allowthecell's function
theevolutionof largercellsafter theevolutionof smallercells
theobservation thatsmallercells usuallyhavea biggercellvolume
thedifferencein plasma membranes between prokaryotesand eukaryotes
theevolutionof eukaryotesafter theevolutionof prokaryotes
An example ofa hydrogen bondis thebond between
46)
_____
CandHin methane(CH ). 4
theHofonewater moleculeandthe Oofanotherwater molecule.
thetwohydrogen atomsina moleculeof hydrogengas (H ). 2
+ Mg andCl in MgCl . 2
+ Na andCl in salt.
Onerole ofRNA isto
47)
_____
makeacopyof itself,thus ensuringgenetic continuity.
functioninthe synthesisof protein.
helpDNAbecome doublestranded
form glycoproteinsand glycolipidsinthe Golgi
catalyzethe hydrolysisof sucrose SHORT ANSWER. Writetheword orphrasethat bestcompletes eachstatement oranswersthe question. RefertoFigure 5.6toanswerthe following questions.
Figure5.6
Which bondisa peptide bond?
48)
________ _ MULTIP LE CHOIC E. Choose theone alternati vethat best complete sthe statemen tor answers the question.
Under whichof the following condition swould you expectto findacell witha predomin anceof free ribosome s?
49)
_____
acellthatis producing cytoplasmic enzymes
acellthatis digestingfood particles
acellthatis secretingproteins
acellthatis enlargingits vacuole
acellthatis constructingits cellwallor extracellular matrix
Ina single molecule ofwater, two hydrogen atomsare bondedto asingle oxygen atomby
50)
_____
hydrogenbonds.
vanderWaals interactions.
nonpolarcovalent bonds.
ionicbonds.
polarcovalent bonds