j j j j j j j
HAPTER 1: CELLS ANDGENOMES
j j j j
©jGarlandjSciencej2015
1.
Scientistsjdiscoverjmorejthanjtenjthousandjnewjspeciesjofjlivingjorganismsjeveryjyear.jW
hatjisjsharedjbetweenjalljofjthesejorganisms?
A. Theyjarehmadejofjcells,jwhosehnucleijenclosejtheirjDNA.
B. Theyjobtainjtheirjenergyjfromjsunlight.
C. Theyjproducehandhusejadenosinejtriphosphateh(ATP).
D. Theirjgenomejcontainsjatjleastj1000jgenes.
E. Alljofjthejabove.
2. Alljcellsj…
A. havejmembranejtransportjproteins.
B. synthesizejproteinsjonjthejribosome.
C. replicatejtheirjgenomejbyjDNAjpolymerization.
D. transcribejtheirjgeneticjinformationjbyjRNAjpolymerization.
E. Alljofjthejabove.
3.
ImaginejajsegmentjofjDNAj(withinjajgene)jencodingjajcertainjamountjofjinformationjinjits
nucleotidejsequence.jWhenjthisjsegmentjisjfullyjtranscribedhintojmRNAjandjthenjtranslatedhintojprote
in,jinjgeneral,j…
A.
thejproteinjsequencejwouldhcarryjmorehinformationjcomparedjtojthejDNAjandjmRjNAj
sequences,jbecausejitsjalphabetjhasj20jletters.
B.
thejproteinjsequencejwouldhcarryjlessjinformationjcomparedjtojthejDNAjandjmRNjAjse
quences,jbecausejseveraljcodonsjcanjcorrespondhtojonejaminojacid.
C.
thejamountjofjinformationjinjthejmRNAjsequencejisjlower,jbecausejthejmRNAjhasjbee
njtranscribedjusingjonlyjonejofjthejDNAjstrandsjasjthejtemplate.
, D.
thejamountjofjinformationjinjthejmRNAjsequencejisjhigher,jbecausejseveraljmRNjAjm
oleculesjcanjbejtranscribedjfromjonejDNAjmolecule.
4.
WhichjofjthejfollowingjprocessesjthatjhappensjinsidejajcelljDOESjNOTjnormallyjrequire
consumptionjofjfreejenergyjbyjthejcell?
A. Replicationjofjthejgeneticjmaterial
B. Importjofjnutrientsjfromjthejenvironment
C. Diffusionjofjsmalljmoleculesjwithinjthejcell
D. Regulationjofjgenejexpression
E. Synthesisjofjenzymesjthatjcatalyzejcellularjreactions
5. WhichjofjthejfollowingjwouldjyoujNOTjexpectjtojfindjinjajbacterialjcell?
A. Swimmingjusinghflagella
B. Havingjajcelljwalljaroundjthehplasmajmembrane
C. ATPjproductionjinjmitochondria
D. Proteinjproductionjonjthejribosome
E. SexualjexchangejofjDNAjwithjotherjbacteria
6.
Tojtracejfamilyjrelationshipsjbetweenjdistantlyjrelatedjorganismsjsuchjasjhumans,jalgae,jb
acteria,jandjarchaea,jonejshouldjcomparejtheirjgenomesjinjregionsj…
A. thatjevolvejrapidly.
B. thatjhavejajhigherjmutationjrate.
C. thatjcodejforjproteins.
D. wherejmutationsjarehhardlyjtolerated.
E. wherejmostjmutationsjarehselectivelyjneutral.
7.
LaboratoryjstrainsjofjthejmodeljorganismjEscherichiajcolijthatjarejresistantjtojantibiotics
arejveryjoftenjusedjinjresearchjlaboratoriesjasjwelljasjinjthejbiotechnologyjindustry.jIfjculturesjofjsjuchjb
acteriajwerejallowedjtojcontaminatejthejenvironmentjuncontrollably,jitjisjpossiblejthatjatjsojmejpoint,j
pathogenicjbacteriajsuchjasjNeisseriajmeningitidisj(whichjcausesjmeningitisjandjcanjcajusejdeath,jesp
eciallyjinjchildren)jcouldjacquirejthejsamejantibiotic-
resistancejgene,jcausinghajmeningitisjoutbreakjthatjisjdifficultjtojtreat.jInjthisjscenario,jwhichjofjth
,ejfollowingjmechanismsjisjajmorejlikelyjsourcejofjthejantibiotic-
jresistancejgenejinjN.jmeningitidis?
A. Randomjnewjgenehgeneration
B. Intragenicjmutation
C. Genejduplication
D. DNAjsegmentjshuffling
E. Horizontaljgenehtransfer
8. Ajvirusj…
A. isjajtypejofjcell.
B. hasjgeneticjmaterialjmadejofjproteins.
C. canjonlyjinfectjajsinglejhostjspecies.
D. canjactjasjajvectorjforjgenejtransfer.
E. cannotjpersistjinjitsjhostjforjmorehthanjonejcelljgeneration.
9. WhichjofjthejfollowingjdoesjNOTjtypicallyjinvolvejhorizontaljgenejtransfer?
A. Sexualjreproductionjinjhumans
B. Bacteriophagejinfectionjofjbacteria
C. ThejevolutionaryjhistoryjofjthejeukaryoticjcelljD
.
Thejaccidentaljduplicationjofjajsmalljregionjofjajbacterialjchromosomejfollowedjbjyjce
lljdivision
E.j Introductionjofjplasmidsjintojbacteriajinjajlaboratory
10.
Genejduplicationjcanjgivejrisejtojhomologousjgenesjthatjarejpartjofjgenejfamilies.jForjexa
mple,jtherejarejsixjactinjgenesjinjthehgenomejofjmostjmammalianjspecies.jInjhumans,jthejACTBjgjene,j
whichjencodesjajcytoskeletaljactin,jisjexpressedjubiquitously,jwhilehACTC1jisjexpressedjmaijnlyjinjca
rdiacjcells.jAlthoughjbacteriajlackjthejeukaryoticjcytoskeletaljorganization,jthejbacterialjMreBjgenejb
earsjrecognizablejsequencehsimilarityjtojmammalianjactinjgenesjandjcodesjforjajprotejinjthatjisjsimilarjt
ojactinjinjstructurejandjfunction.jWhichjofjthejfollowingjstatementsjisjtruejaboutjthesejgenes?
A. ACTBjisjhomologousjtojACTC1jbutjnotjtojMreB.
B. ACTBjisjorthologousjtojACTC1jbutjnotjtojMreB.
C. ACTBjisjparalogousjtojACTC1jbutjnotjtojMreB.
D. MreBjisjorthologousjtojACTBjbutjnotjtojACTC1.
, E. ACTBjisjparalogousjtojbothjACTC1jandjMreB.
11. Outjofjnearlyj5000jprotein-
codingjgenejfamilies,jtherehisjajsetjofjnearlyj300jconservedjgenejfamiliesjthatjarejfoundjinjspeciesjfromj
alljdomainsjofjlife.jWhenjonejlooksjatjthejgeneraljfunctionsjassignedjtojthesejgenejfamilies,jijtjisjfoundjt
hatj…
A. thejmajorityjofjthemjfunctionjinjcell-to-celljsignaling.
B. thejmajorityjofjthemjarejpoorlyjcharacterized.
C. morejthanjone-
thirdjofjthemjarejinvolvedjinjtranslationjorjaminojacidjtransportjandjmetabolism.
D. morejthanjone-
halfjofjthejsharedjfamiliesjarejinvolvedjinjDNAjreplicationjandjtranscription.
E. Nearlyjalljofjthemjarejinvolvedjinjenergyjproductionjandjcarbohydratejmetabolism.
12. WhichjofjthejfollowingjisjtruejregardinghEscherichiajcoli?
A. Mostjofjourjunderstandinghaboutjmitosisjcomesjfromjstudiesjonjthisjmodeljorganism.
B. Itjisjajrod-
shapedjbacteriumjthatjcanjonlyjgrowjinjthejgutjofjhumansjandjotherjvertebrates.
C. TwojstrainsjofjE.jcolijcanjdifferjbyjupjtoj0.1%jinjtheirjgenomes.
D. E.jcolijstrainjK-12jencodesjaboutj4300jproteins.
E. ThejE.jcolij(strainjK-12)jgenomejisjaboutj430jmillionjnucleotidejpairsjlong.
13. WhichjofjthejfollowingjisjNOTjtruejregardingjthejtreehofjlife?
A. Mostjbacteriajandjarchaeajhavej1000jtoj6000jgenesjinjtheirjgenomes.jB.
Eukaryotesjarejmorejsimilarjtojarchaeajthanjtojbacteriajwithjrespectjtojthejproteinsjthatja
ctjonjtheirjDNA.
C.
Mostjbacteriajandjarchaeajhavejgenomejsizesjbetweenjonejandjtenjmillionjnucleotijdejp
airs,jwhereasjeukaryoticjgenomesjcanjbejmillionsjofjtimesjlarger.
D.
Archaealjspeciesjwerejthoughtjtojbelongjtojthejeukaryoticjworldjbeforehsequencejajnaly
sisjplacedjthemjinjajseparatejdomainjofjlife.
E.j Photosyntheticjbacteriajarejthoughtjtojbejthejancestorsjofjthejeukaryoticjchloroplasts.