GeneticsBiol360FinalExamFall2010 100pts

Name:_______________________________________
Multiplechoice.Choosetheonebestanswerforeachquestion.70questions,eachworth~1.4pts.

1. GivenaDNAmoleculethatwas6basepairsinlength,howmanydifferentsequencescouldbeproduced?
a. 6
b. 1024
c. 4096
d. 3.2x106
e. 6.4x107

2. Givenapolypeptidethatwas6aminoacidsinlength,howmanydifferentsequencescouldbeproduced?
a. 6
b. 1024
c. 4096
d. 3.2x106
e. 6.4x107

3. E.coliarefedradioactive32phosphorous(32P)andtheninfectedwithbacteriophageT2.Thephagedivideinsidethe
E.coliandcausethemtoburst,orlyse.Thephagearerecoveredandthenusedtoinfectanavebatchofnon
radioactiveE.coli.Afterincubation,whereisthe32Pfound?
a. Nowhere.ItslostwhentheE.colilyse.
b. Mostlyitsfoundinsidethephage.
c. Mostlyitstaysonthebacterialcellwall.
d. MostlyitsfoundinsidetheE.coli.
e. Mostlyitsfoundonthephageheadcapsid.

4. Inhisexperiment,Taylorlabeledthetipsofbeanrootswith3Hthymidine.Thesetipsgrowrapidlyandsohewas
abletovisualizemitoticchromosomeseasilyusingautoradiographs.Whatdidthesechromosomeslookslikein
prophaseafteroneroundofDNAreplicationin3Hthymidine?(*asterisksrepresentradioactivity)
a.
b.
c.

d.

e.

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5. Taylorthenremovedtheunincorporated3Hthymidineandallowedthecellstoundergoanotherroundof
replication.Whatdidthesemitoticchromosomeslooklike?
a.

b.

c.

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6. Whichofthefollowingbondsrepresentsthephosphodiesterbond?

7. ThelowerrorrateinDNAreplicationisduetoDNApolymerases
a. 53polymeraseactivity
b. 53ligaseactivity
c. 53exonucleaseactivity
d. 35exonucleaseactivity
e. 35polymeraseactivity

a.

b.

c.

e.

d.

8. Whichofthefollowingstructuresisadeoxyribonucleotide?
a.

b.

c.

e.

d.

9. Antiparallelmeansthat
a. DNAstrandsruninoppositedirections.
b. DNAstrandsarenotstraight.
c. DNAstrandsarenotparallel.
d. thereisnocytosineinDNA.
e. thereisnothymineinRNA.

10. HowmanyhydrogenbondswouldformbetweentheDNAsequenceCAGTTanditscomplementontheotherstrand
inadoublehelix?
a. 5
b. 10
c. 12
d. 13
e. 15

11. PrimaseisanRNApolymerasewhichsynthesizestheRNAprimeronthelaggingstrandduringDNAreplication.RNA,
andnotDNA,isusedastheprimerbecause
a. DNApolymerasehasexonucleaseactivity,andRNApolymerasedoesnt
b. DNApolymerasesynthesizesDNAonlyinthe53direction
c. DNApolymeraserequiresa3OHgroup,andRNApolymerasedoesnt
d. RNApolymerasesynthesizesonlyasinglestrandofnucleotidesatatime,andDNApolymerasedoesnt
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e. RNApolymerasesynthesizesRNAonlyinthe35direction

12. ThetransformingsubstanceofStreptococcuspneumoniaewasshownbyAveryetal.tobe
a. protein
b. carbohydrate
c. lipid
d. DNA
e. RNA

13. WhichofthefollowingpairofprimerscouldbeusedtoPCRamplifyafragmentofthefollowingDNAsequence?

5'TACGGCTGCGAGAAGACGACAGAAGGGGGAGAGAGGGTGAGTGTGTGTGAGTGCATGGGAGGGTGCTGAA
3'ATGCCGACGCTCTTCTGCTGTCTTCCCCCTCTCTCCCACTCACACACACTCACGTACCCTCCCACGACTT
TATTCCGAGACACTGGGACCACAGCGGCAGCTCCGCTGAAAACCGCATTCAGCCAGTCCTCCGGACTTCT3'
ATAAGGCTCTGTGACCCTGGTGTCGCCGTCGAGGCGACTTTTGGCGTAAGTCGGTCAGGAGGCCTGAAGA5'
a. 5'ATGCCGACGC3'and5'CCGGACTTCT3'
b. 5'GGCTGCGAGA3'and5'AAGTCCGGAG3'
c. 5'GACACTGGGA3'and5'CTCTGTGACC3'
d. 5'TACGGCTGCG3'and5'ATGCCGACGC3'
e. 5'TACGGCTGCG3'and5'CCGGACTTCT3'

14. OneoftheearlycluesforanRNAintermediatebetweenDNAandproteinwasthat
a. RNAissinglestranded,whereasDNAisdoublestranded
b. proteinsareencodedbygenes
c. DNAisstable,whileRNAisnot
d. RNAcontainscodonswhichspecifyaminoacids
e. DNAisnuclear,whereasproteinsarecytoplasmic

15. GiventhatthepromoterandcodingstrandofabacterialgenehadthefollowingDNAsequence,whatwouldthe
sequenceofthemRNAbe?
5'GCATGGGTAGGCCTATAATGCAGGAGGATGGTAAACTAGGAGGCCTTATGATTTTTGG3'
a. 5GAUGGUAAACUAGGAGGCCUUAUGAUUUUUGG3
b. 5CUAGGAGGCCUUAUGAUUUUUGG3
c. 3mG55GAUGGUAAACUAGGAGGCCUUAUGAUUUUUGGAAAAAAAAAAAAAAA3
d. 5'GCAUGGGUAGGCCUAUAAUGCAGGAGGAUGGUAAACUAGGAGGCCUUAUGAUUUUUGG3'
e. 3mG55'GCAUGGGUAGGCCUAUAAUGCAGGAGGAUGGUAAACUAGGAGGCCUUAUGAUUUUUGGAAAAAAA3'

16. TranscriptionofDNAintomRNAiscatalyzedby
a. RNApolymerase
b. DNApolymerase
c. RNase
d. ribonuclease
e. ribosomes

17. Aeukaryoticgenespans600,000basepairsofDNA,fromthetranscriptionstartsitetothestopsite.Thereare10
exons,andtheaveragelengthofanexonis100basepairs.HowlongistheunprocessedRNAmoleculeproduced
fromthisgene?
a. 100nucleotides
b. 1000nucleotides
c. 600,000nucleotides
d. 601,000nucleotides
e. Cannotbedeterminedfromtheinformationgiven

18. ThesameeukaryoticgeneisprocessedintomRNA.HowlongistheresultingmRNA?
a. 100nucleotides
b. 1000nucleotides
c. 600,000nucleotides
d. 601,000nucleotides
e. Cannotbedeterminedfromtheinformationgiven

19. Thesameeukaryoticgeneistranslatedintoprotein.HowlongisthecodingregionofthemRNA?
a. 100nucleotides
b. 1000nucleotides
c. 600,000nucleotides
d. 601,000nucleotides
e. Cannotbedeterminedfromtheinformationgiven

20. Thetertiarystructureofaproteinis
a. thefoldingofthepeptidechainintoaglobularprotein.
b. thecoilingorfoldingofapeptidechainintoahelixorpleatedsheet.
c. thebondingoftwoaminoacidstogethertoformadipeptide.
d. theorderinwhichaminoacidsarejoinedinapeptidechain.
e. thebondingtogetherofseveralpolypeptidechainsbyweakbonds.

21. Thefactthatagivenaminoacidmayhavemorethanonecodoniscalled
a. degeneracy.
b. ambiguity.
c. redundancy.
d. familymixing.
e. wobble.

22. GivenanmRNAmoleculewiththesequence5AUAUAUAUAUAUAUAU.3,whattypeofpolypeptide(s)wouldyou
expecttoproduceinaninvitrotranslationreaction?(Assumetranslationinitiationisrandom.)
a. NH2IleTyrIleTyrIleTyrIleTyrIleTyrIleTyrIleTyr..COOH
b. NH2IleTyrTrpIleTyrTrpIleTyrTrpIleTyrTrpIleTyrTrpCOOH
c. NH2IleIleIleIleIleIleIleIleIleIleCOOHandNH2TyrTyrTyrTyrTyrTyrTyrTyrCOOH
d. NH2IleIleIleIleIle.COOH;NH2TyrTyrTyrTyrCOOH;andNH2TrpTrpTrpTrpTrpCOOH

23. TransferRNAisimportantintranslationbecause
a. itistransient.
b. itisfoundinboththenucleusandthecytoplasm.
c. ribosomescanreadthetRNAandtranslateitssequenceintoaprotein.
d. itcanbindbothaminoacidsandRNA.
e. itcanbindtopromoterDNA.

24. Cysticfibrosisisconsideredarecessivehumandiseasebecause
a. themutantalleleisfoundinasmallpercentageofthepopulation
b. thedominantalleleisfoundinalargepercentageofthepopulation
c. themutantalleleisoverpoweredbythedominantallele
d. themutantphenotypeismaskedinheterozygotes
e. thedominantphenotypeismaskedinheterozygotes

25. CysticfibrosisiscausedbyamutationinthegeneCFTR,achloridechannel.Cysticfibrosisisconsideredarecessive
humandiseasebecause
a. acellthatexpressesthemutantchloridechannelcannotmaintainproperosmoticbalance
b. acellthatexpressesonlyhalfthenumberofnormalchloridechannelscanmaintainproperosmoticbalance.
c. acellthatexpressesnochloridechannelscanmaintainproperosmoticbalance.
d. thenormalchloridechanneloverpowersthemutantchannel
e. themutantchloridechannelisexpressedbutnotfunctional

26. Huntingtonsdiseaseiscausedbyapolyglutamineexpansionwhichcausesthehuntingtinproteintomisfoldand
formplaquesinneurons,therebydisruptingtheirphysiology.Huntingtonsdiseaseisconsideredadominanthuman
diseasebecause
a. plaquesformintheneuronsofpeoplewithnomisfoldedproteins.
b. withtwomutantcopiesofthegene,plaquesforminpatientsneurons
c. evenwithonegoodcopyofthegene,plaquesstillform.
d. plaquestendtoformlateinlife,pastreproductiveage
e. withtwogoodcopiesofthegene,plaqueswillnotform

27. Mostmutationsare
a. harmful
b. beneficial
c. weaklybeneficial
d. neutral
e. harmfulorbeneficial,dependingupontheenvironment

28. ThefollowingmRNAsequencerepresentsonlythecodingportionofagene.
5AUGCUGGAACAAGGGCGAUAA3
Whattypeofpolypeptidemutationwouldresultifthefollowinginsertionwasmade?
5AUGGCUGGAACAAGGGCGAUAA3
a. insertion
b. missense
c. frameshift
d. transversion
e. silent

29. AkeydifferencebetweenretrotransposonsandDNAtransposonsisthat
a. retrotransposonsarefoundprimarilyinheterochromatin,whereasDNAtransposonsarenot
b. retrotransposonsareconsideredjumpinggenes,whileDNAtransposonsarenot
c. retrotransposonsuseareplicativemodeofjumping,whileDNAtransposonsdonot.
d. retrotransposonsusetransposasetojump,whileDNAtransposonsdonot.
e. retrotransposonsarefoundinsideofgenes,whileDNAtransposonsarenot.

30. Inthehumangenome,approximatelyhowmuchoftheDNAencodesforproteins?
a. 1.5%
b. 15%
c. 50%
d. 75%
e. 99.9%

31. AnexampleofsatelliteDNAisa
a. multicopygene
b. LINE
c. SINE
d. retrotransposon
e. centromere

32. Inthehumanpopulation,themicrosatellitesequenceCAisfoundrepeatedbetween5and20timesataparticular
locus.Awomanisheterozygousatthislocus,havingonecopywhichisrepeated8times,andanothercopyrepeated
12times.Herchildisalsoheterozygous,havingonecopywhichisrepeated12times,andonecopywhichis
repeated16times.Listedbelowarethegenotypesofthepossiblefathers.Whichofthefollowingisthechilds
father?
a. (CA)8/(CA)8
b. (CA)12/(CA)12
c. (CA)8/(CA)12
d. (CA)10/(CA)12
e. (CA)10/(CA)16

33. ThemicrosatellitesequenceATGGisrepeatedbetween5and15timesataparticularlocusincorn.Yellowkernels
aredominanttopurplekernelsinthesamecornspecies.Truebreedingcornwithyellowkernelsandmicrosatellite
(ATGG)5iscrossedwithtruebreedingcornwithpurplekernelsandmicrosatellite(ATGG)15,resultinginF1plants
thathaveyellowkernelsandareheterozygous(ATGG)5/(ATGG)15.

TheF1plantsareselfcrossed.WhataretheexpectedratiosoftheF2offspringifthetwolociareunlinked?
a. 3yellow,5/5:1purple,15/15
b. 3yellow,5/5:3yellow,15/15:1purple,5/5:1purple,15/15
c. 1yellow,5/5:1yellow,15/15:1purple,5/5:1purple,15/15
d. 3yellow,5/5:6yellow,5/15:3yellow,15/15:1purple,5/5:2purple,5/15:1purple,15/15
e. 9yellow,5/15:3yellow5/15:3purple,5/15:1purple,5/15

34. Whichseriesprogressesfromthethinnesttothethickestindiameter?
a. DNA>histone>chromosome>nucleosome
b. histone>chromosome>DNA>nucleosome
c. nucleosome>histone>DNA>chromosome
d. DNA>histone>nucleosome>chromosome
e. Noneofthesearecorrect.

35. ThegeneFOXP2playsaroleinanimaldevelopment,andspecificallyinhumanshasbeensuggestedtocontributeto
theuseofspeechandlanguage.Examinethefollowingsequencealignmentfromseveralspecies,whichisaportion
oftheFOXP2gene.
Human
AAGGCTATTACGATCCGG
Chimpanzee
AAGGCTACAACGATCCGG
Squirrel Monkey
AAGGCTACAACGAACCGG
Dog
ATAGCTACAACGAACCGG
Mouse
ATAGCTACAACGAACCCG
Chicken
TTAGCTACAACAAACCCC

Basedonthismultiplesequencealignment,isitatleastpossiblethatFOXP2playsaroleinhumanspeech?
a. Yes,becausethereisahumanspecificsequenceinFOXP2.
b. Yes,becausethereisaprimatespecificsequenceinFOXP2
c. No,becausethehumanspecificsequenceinFOXP2ismutated.
d. No,becausetheFOXP2sequenceiscommontoallanimals

36. Homologousgenes
a. pairupduringmeiosis
b. are99.9%similarinsequence
c. arefoundonthematernalandpaternalchromosomes
d. arisebygeneduplication
e. produceproteinswhichareunlikeoneanother

37. Whileexaminingakaryotypeofacancerpatient,younoticethatoneofthechromosome7sisslightlyshorterthan
itshouldbe,andthatoneofthechromosome16sisslightlylonger.Themostlikelyexplanationforthisis
a. achromosome7deletionandchromosome16duplication
b. areciprocaltranslocationbetweenchromosomes7and16.
c. achromosome7and16inversion
d. achromosome7nonsensemutationandchromosome16frameshiftmutation
e. achromosome7nonsensemutationandchromosome16missensemutation

38. Duringthecellcycle,separationofthechromosomestakesplaceduringwhichstage?
a. S
b. G2
c. M
d. G1
e. G0

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39. Thecentromericregionofachromosomerefersto
a. aregionateachendofthechromosomethatisdifferentfromtherestofthechromosome.
b. aconstrictedareawherethesisterchromatidsarejoinedtogether.
c. themiddleofeachchromosome.
d. theregionofthechromosomethatisgeneticallyactive.
e. scatteredregionsofthechromosomethatstaindifferentlyandareusuallyinactiveintranscription.

40. Referringtothepicturebelow,whichisthestatementthatbestdescribesthiscell?
a. Ahaploidcell,withtwochromosomes
b. Ahaploidcell,withfourchromosomes
c. Adiploidcell,withtwochromosomes
d. Adiploidcell,withfourchromosomes
e. Atetraploidcell,withfourchromosomes

41. Referringtothepicturebelow,whichisthestatementthatbestdescribesthiscell?
a. Ahaploidcell,withtwochromosomes
b. Ahaploidcell,withfourchromosomes
c. Adiploidcell,withtwochromosomes
d. Adiploidcell,withfourchromosomes
e. Atetraploidcell,withfourchromosomes

42. Referringtothepicturebelow,whichisthestatementthatbestdescribesthiscell?
a. Ahaploidcell,with6chromosomes
b. Adiploidcell,with2chromosomes
c. Adiploidcell,with6chromosomes
d. Atriploidcell,with2chromosomes
e. Atriploidcell,with6chromosomes

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43. ForanindividualwhohasthegenotypeAaBb,whatistheprobabilitythatoneoftheirgameteswillcontainthe
allelesAa?
a. 0
b.
c.
d.
e. 1

44. Atallanddwarfpeaplantarecrossedresultinginalltallplants.TheF1tallplantsareselfcrossed.Whatarethe
approximateratiosofthegenotypesfortheF2offspring?
a. 3:1
b. 9:3:3:1
c. 1:1:1:1
d. 1:1
e. 1:2:1

45. ThegeneforredopsinisontheXchromosomeinprimates.Recessivemutationsinthisgenecauseredgreencolor
blindness.Afemalecarrierformutantopsinandanormal,trichromaticvisionmalehavekids.Whatisthe
probabilitythatoneoftheirkidsisaboywithredgreencolorblindness?
a. 0
b.
c.
d.
e. 1

46. Inhumans,theYchromosomedeterminesmalenessbecause
a. theratioofXchromosomestoautosomesis

b. theratioofXchromosomestoautosomesis1
c. theratioofXtoYchromosomeis1
d. theXchromosomeisinactivatedasaBarrbody
e. theYchromosomecontainstheSRYgene

47. Duringgametogenesis,awomansprogenitoroocytefailstoundergocytokinesisfollowingmeiosisI.Whenthe
developedeggisfertilizedbyanormalhaploidsperm,whatwillbethekaryotypeoftheresultingzygote?
a. Haploid
b. Diploid
c. Triploid
d. Tetraploid
e. Normalkaryotype

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48. InadditiontotheF508mutationthatcausescysticfibrosis,thereare15otherpointmutationsand8other
deletionmutationsintheCFTRgenethatcausethedisease.HowmanyallelesfortheCFTRgeneexistinthe
population?
a. 1
b. 2
c. 15
d. 23
e. 25

49. Anotherwisenormalboyisdiagnosedwithcysticfibrosis.HowmanyallelesfortheCFTRgenedoeshehave?
a. 1
b. 2
c. 15
d. 23
e. 25

50. Twogeneswillnotexhibitlinkageingeneticcrossesif
a. theyareneareachotheronthesamechromosome.
b. therateofrecombinationbetweenthemislessthan0.5.
c. theyareondifferentchromosomes.
d. allofthesechoicesaretrue.
e. noneofthesechoices

51. Twoblackguineapigswerematedandoverseveralyearsproduced29blackand9whiteoffspring.Themostlikely
genotypesfortheparentsare
a. bbandbb
b. BBandBB
c. Bbandbb
d. BbandBb
e. BBandbb

52. Awildtypeandacurlywingedflyarecrossed,resultinginhalfcurlywingedfliesandhalfwildtypeflies.TheF1curly
wingedfliesarecrossedgivinganF2offspringratioof2curlywinged:1wildtype.Themostlikelyexplanationfor
thisresultis:
a. wildtypeisdominanttocurlywings
b. curlywingsisrecessivelethal
c. curlywingsisepistatictowildtype
d. curlywingshashighpenetrance
e. wildtypeandcurlywingsshowincompletedominance

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53. ThecrossAaBbxaabbiscalleda
a. reciprocalcross
b. testcross
c. dihybridcross
d. backcross
e. monohybridcross

54. Inoneclassin1914,heightofmalecadetsrangedbetween410to62,withthemeanbeing58.In2010,a
similarsizedclassofmalecadetsshowedaheightvariationbetween54to65,withthemeanbeing510.The
increaseinheightscanbestbeexplainedby
a. increasedgeneticvariance
b. increasedenvironmentalvariance
c. increasedheritability
d. decreasedheritability
e. betternutrition

55. Monozygotictwins(identical)areapproximately60%concordantforautism,whereasdizygotictwins(fraternal)are
approximately8%concordant.Fromthesenumbers,youwouldpredictthatautismhas
a. heritability=1
b. highheritability(>0.5)
c. averageheritability
d. lowheritability(<0.5)
e. heritability=0

56. Fromthissametwinstudyofautism,youcanpredictthat
a. genesdonotinfluenceautism
b. environmentdoesnotinfluenceautism
c. geneticsexplains60%ofautism
d. environmentexplains8%ofautism
e. insufficientdatatomakeaprediction

57. Whenatraithasacontinuousdistribution,suchasheight,andmostindividualsinthepopulationarenearthe
average,thedistributionofthetraitismostlikelya(n)_____distribution.
a. dominant
b. recessive
c. epistatic
d. normal
e. additive

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58. Ifheightinplantswascontrolledbythreeadditivegenes,A,B,andC,acrossofanintermediateplantwitha
genotypeofAaBBccwithanintermediateplantwithagenotypeofAabbCC,wouldproducewhatratiosofheightsin
theoffspring?
a. 1:6:15:20:15:6:1
b. 27:9:9:9:3:3:3:1
c. 1:2:1
d. 1:1:1:1:1:1::1:1
e. 1:4:6:4:1

59. Aninbredstrainofplantshasameanheightof10cm.Asecondinbredstrainhasaheightof42cm.Crossingthetwo
strainsproducesanF1thathasameanheightof26cm.TheF2haveacontinuousrangeofheightswasobserved
withmostplantsaround30cmand4outof1000at10cm,and4outof1000at42cm.Howmuchdoeseach
additiveallelecontributetoheight?
a. 1cm
b. 2cm
c. 3cm
d. 4cm
e. 5cm

60. Inwheat,seedcolorisapolygenictrait(additivemodel).Iftruebreedingredandwhitevarietiesarecrossed,theF1
areintermediateincolor.IftheF1areselffertilized,about1in1000havewhiteseeds.Howmanylociare
segregatingcoloralleles?
a. 1
b. 2
c. 3
d. 4
e. 5

61. Twotruebreedingtobaccostrainswerecrossed,onewithlongcorollas(flowerpetals)andonewithshort.TheF1
generationresultedinadistributionofcorollalengths,withanaverageof50mm.Next,anF1xF1selfcrosswas
performedwithaplanthavingcorollas54mmlong.TheresultingF2generationhadadistributioninlength,withan
averageof51mm.Whatisthenarrowsenseheritabilityofcorollalengthinthistobaccostrain?
a. 0.25
b. 0.5
c. 0.7
d. 1.0
e. 2.0

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62. AtallparentandashortparentproduceintermediateF1offspringthat,whenselffertilized,producearangeof
offspringheights,sometallerthanthetallP1andsomeshorterthantheshortP1.Whichsetofparentalgenotypes
couldaccountforthesedata?
a. AABBCCxaabbcc
b. AABBxaabb
c. AABBccxaabbCC
d. AABBCCxAABBCC
e. AAbbccxAAbbcc

63. Twoaverageheightparentshaveseveralchildren,allaboutthesameaverageheightastheirparents.Whichsetof
parentalgenotypescouldaccountforthesedata?
a. AABBCCxaabbcc
b. AABBxaabb
c. AABBccddxaabbCCDD
d. AabbCCDdxAaBBCCDd
e. AaBbCcDdxAaBbCcDd

65. Whenstudyingquantitativetraitssuchasheight,thetermheritabilityrefersto
a. theenvironmentalvariance.
b. thegeneticvariance.
c. Thefractionofthephenotypicvariancethatiscausedbygeneticvariance.
d. howmuchofthetraitisdeterminedbygenetics.
e. totalgeneticvariance

66. Haircolorisanexampleofatrait
a. thatcanhavehighorlowheritability,dependingonthepopulation
b. thathashighheritability,becausehaircolorisdeterminedbygenetics.
c. thathaslowheritability,becausehaircolorcanbedeterminedbytheenvironment
d. thatwillhavehighheritabilityinaninbredpopulation,duetosimilargeneticsbetweenindividuals
e. thatwillhavelowheritabilityinanoutbredpopulation,duetoasmallnumberofallelesinthepopulation

67. Inthe1970s,PeterandRosemaryGrantstudiedfinchbeaksizeononeoftheGalapagosislands.Duringsevere
droughtstheydiscoveredthataveragebeaksizeincreased,possiblyasaresponsetochangingfoodsources.From
thisinformation,onecansaythatthedroughtcaused
a. increasedenvironmentalvariance
b. increasedgeneticvariance
c. directionalselection
d. disruptiveselection
e. stabilizingselection

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68. IntheEvolutionlab,precipitationdriveswhatkindofselection(s)infinchbeaksize?
a. directional
b. disruptive
c. stabilizing
d. directionalorstabilizing,dependingupontheprecipitationlevel
e. disruptiveorstabilizing,dependingupontheprecipitationlevel

69. IntheEvolutionlab,increasingvarianceinbeaksizecauses
a. strongerselection
b. weakerselection
c. afasterrateofevolution
d. aslowerrateofevolution
e. afasterrateofevolution,followedbyaslowerrate

70. Experimenttoexperimentvariabilitycanbedecreasedby
a. decreasingthevariance
b. decreasingtheheritability
c. decreasingprecipitation
d. extendingthetimefrom100to300years
e. startingwithalargerpopulationoffinches

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