阅读解析tpo31 rTPO小站出国留学考试第一社区

TPOQ1ThewordQ1Theword”promotes”inthepassageclosestinmeaning>Evolutionarybiologistsbelievespeciationspeciationinvolveswhichoftheparagraph1,Q2According Thereunitingofseparatedpopulationsaftertheyhave edistinctspeciesThemovementofapopulationtoanewTheabsenceofgeneflowbetweenParagraph1ismarkedwithan

speciation,theformationofanewspecies,oftenbeginswhensomekindofphysicalbarrierarisesanddividesapopulationofasinglespeciesintoseparatesubpopulations.Physicalseparationbetweensubpopulationspromotestheformationofnewspeciesbecauseoncethemembersofonesubpopulationcannolongermatewithmembersofanothersubpopulation,theycannotexchangevariantgenesthatariseinoneofthesubpopulations.Intheabsenceofgeneflowbetweenthesubpopulations,geneticdifferencesbetweenthegroupsbegintoaccumulate.Eventuallythe esogeneticallydistinctthattheycannotinterbreedevenifthephysicalbarriersbetweenthemwereremoved.Atthispointthesubpopulationshaveevolvedintodistinct

批注[1]:正确答案：B解析：promote本身是促进的是subpopulations间的物理分割…了新物种的形成，A描所以B最合适的。批注[2]:正确答案：D解析：根据allopatric进行定A与原文不附，原文说的是物理barrier把population分割成subpopulationB也不对，对应Eventually这句。C原文没提到。DIntheabsence开始到最后。Q3Q3Whydoestheauthorprovideinformationthat“thesubpopulationsofmostspeciesareseparatedfromeachothersomemeasurablespecies.ThisroutetospeciationisTodefinewhatitmeansforagroupofanimalsorntstobeasubpopulationTosuggestthatallopatricspeciationisnottheonlyroutetospeciation

asallopatry(“allo‐”means“different”,and“patria”means“homeland”).>Allopatricspeciationmaybethemainspeciationroute.Thisshouldnotbesurprising,sinceallopatryisprettycommon.Ingeneral,thesubpopulations

句），allopatry是mainspeciationroute。本段都是围选择DTohelpexinwhyallopatricspeciation

ofmostspeciesareseparatedfromeach批注 acommonwayfornewspeciestocomeQ4Theword”accumulate”inthepassageisclosestinmeaningtoemoreOccurGraduallyincreasein

otherbysomemeasurabledistance.Soevenundernormalsituationsthegeneflowamongthesubpopulationsismoreofanintermittenttricklethanasteadystream.Inaddition,barrierscanrapidlyariseandshutoffthetrickle.Forexample,inthe1800samonstrousearthquakechangedthecourseofthe

因的区别开始accumulate。Eventually对理解这个词很有程，gradually更合适。解析：Forexamplebarriers也有可能突然发生，解析：Forexamplebarriers也有可能突然发生，对应的是Q5Inparagraph2,whydoestheauthormentionthatsomeinsectpopulationswereseparatedfromeachotherbyachangeinthecourseofMississippiRivercausedbyTomakethepointthatsomekindofphysicalbarrierseparatesthesubpopulationsofmostspeciesTosupporttheclaimthattheconditionofallopatrycansometimesariseinashortToprovideanexampleofasituationinwhichgeneflowamongthesubpopulationsofaspecieshappensataslowrateToexinwhyinsectslivingalongoppositeshoresoftheMississippiRiverareverydifferentfromeachotherParagraph2ismarkedwithananimalswerereproductivelyisolatedevenaftertheglaciersdisappeared

>Geographicisolationalsocanproceedslowly,overgreatspansoftime.Wefindevidenceofsuchextendedeventsinthefossilrecord,whichaffordsglimpsesintothebreakupofformerlycontinuousenvironments.Forexample,duringpast

根据Glaciers和ntsandanimals定位。红色句子就是hadadjustedtotheoldconditions iceagesglaciersadvanceddownthroughglacierseparationbythewereabletosurvivebeingseparatedfromtheirparentpopulationhadexperiencedsomegeneticdivergencesfromtheirparentpopulationParagraph3ismarkedwithan

NorthAmericaandEuropeandgraduallycutoffpartsofpopulationsfromoneanother.Whentheglaciersretreated,theseparatedpopulationsofntsandanimalscameintocontactagain.Somegroupsthathaddescendedfromthesameparentpopulationwerenolongerreproductivelycompatible—theyhadevolvedintoseparatespecies.Inothergroups,however,geneticdivergenceshadnotproceededsofar,andthedescendantscouldstillinterbreed—forthem,reproductiveisolationwasnotcompleted,andsospeciationhadnot

果。所以对应选项AThemovementsbroughtpopulationsofcertainfishesandmarineorganismsintocontactwithoneanotherforthefirsttime.ThemovementstransferredpopulationsoffishesandothermarineanimalsbetweenthePacificandAtlanticOceans.ThemovementcreatedconditionsthatallowedwatertoflowmorelybetweenthePacificandAtlanticOceans.Themovementcreatedconditionsfortheformationofnewspeciesoffishesandothermarineanimals.Paragraph4ismarkedwithanQ9Theword”sequence”inthepassageisclosestinmeaningto

colossalmovementsofthetectonictesthatmakeupEarth’ssurface.Q7Theword”colossal”inthepassage>AllopatricspeciationcanalsoclosestinmeaningQ7Theword”colossal”inthepassage>AllopatricspeciationcanalsoclosestinmeaningbroughtbytheimperceptiblyslowQ8Accordingtoparagraph4,whichoffollowingistrueofthegeologicthatbroughtabouttheIsthmusofThisdivisionsetthestageforallopatricspeciationamongpopulationsoffishesandothermarinespecies.■>Inthe1980s,JohnGravesstudiedtwopopulationsofcloselyrelatedfishes,onepopulationfromtheAtlanticsideofisthmus,theotherfromthePacificside.Hecomparedfourenzymesfoundinthemusclesofeachpopulation.GravesfoundthatallfourPacificenzymesfunctionbetteratlowertemperaturesthanthefourAtlanticversionsofthe

批注[7]:正确答案：C解析：Colossal本身是巨大的，C选案，与colossal并列的词汇是最后一句说了isthmusofPanama带来的结果，对应了D选项。批注[9]:正确答案：B啊，酶啊，pairs啊什么的，Q10Accordingtoparagraph5,bytheenzymesfromtwoQ10Accordingtoparagraph5,bytheenzymesfromtworelatedgroupsoffishesonoppositesidesoftheGravesfoundevidencetherewereslightgenetic

Pacificseawateristypically2to3degreescoolerthanseawaterontheAtlanticsideofisthmus.ysisbygeldifferencesinaminoacidsequence

betweenthetwo theenzymesoftwoofthefourpairs.This批注 descendedfromthePacificgroupofthetemperatureofwateroneithersideoftheisthmushadchanged geneticchangesintheAtlanticgroupoffishesweremorerapidandfrequentthan

issignificantbecausetheaminosequenceofanenzymeisdeterminedby

inthePacificgroupofParagraph5ismarkedwithanQ11Itcanbeinferredfromparagraph5and6thatthereasonGravesconcludedthatsomeofthedifferencesbetweenthePacificandAtlanticenzymeswerenotrandomwasthat

>Gravesdrewtwoconclusionsfromtheseobservations.First,atleastsomeoftheobserveddifferencesbetweentheenzymesoftheAtlanticandPacificfishpopulationswerenotrandombutweretheresultofevolutionaryadaptation.Second,itappearsthatclosely

eachofthePacificenzymesworksbetter populationsoffishesonbothsidesofthecoolertheEnzymesoftheAtlanticfishpopulationshadnotchangedsincetheformationoftheIsthmusofPanamagelelectrophoresisshowedthatthechangesbenefitedboththeAtlanticand

isthmusarestartingtogeneticallydivergefromeachother.BecauseGraves’sstudyofgeographicallyisolatedpopulationsofisthmusfishesoffersaglimpseofthebeginningofaprocessofgradualaccumulationofmutationsthat

C文章提到gelelectrophoresisPacificfishthedifferencesbetweentheenzymesdisappearedwhenthetwofishpopulationswereexperimentallyswitchedtoothersideoftheisthmus

areneutraloradaptive,divergencesherebenefited。Dmightbeevidenceofallopatricspeciationinprocess.Q12Whichofthesentencebelowbestexpressestheessentialinformationinthehighlightedsentenceinthepassage?Incorrectchoiceschangethemeaninginimportantwaysorleaveoutessentialinformation.Graves’sstudyprovidesevidencethatisthmusfishesareintheprocessof geographicallyisolated.Graves’sstudyofmutatingisthmusfishesyieldsresultsthatdifferfromresultsofotherstudiesinvolvingallopatricspeciation.Graves’sstudyofisolatedpopulationsofisthmusfishesprovidessomeevidencethatallopatricspeciationmightbebeginning.Q13Lookatthefoursquares[■Q13Lookatthefoursquares[■]indicatewherethefollowingsentencemakeupEarth’ssurface.■AboutmillionyearsagosuchbeaddedtothemovementscreatedthelandTheformationoftheisthmushadimportantconsequencesforglobalpatternsofoceanwaterflow.

AllopatricspeciationcanalsobebroughtbytheimperceptiblyslowbutcolossalmovementsofthetectonictesthatbetweenNorthAmericaandSouthAmericathatwecalltheIsthmusofPanama.■Whilepreviouslythegapbetweenthecontinentshadalloweda

CB出现了isthmus，而后面则是Wherewouldthesentencebestfit?Clickonasquaretoaddthesentencetothepassage.

flowofwater,nowtheisthmuspresentedabarrierthatdividedtheAtlanticOceanfromthePacificOcean.Q14Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.SomesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareQ14Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.ThisquestionisworthAllopatricspeciation cephysicallyseparatedpopulationsofasinglespeciesgraduallydivergegenetically