2026年托福《阅读》考试真题(完整版)

2026年托福《阅读》考试真题(完整版)PassageOneTheEcologicalImplicationsofPhenotypicPlasticityPhenotypicplasticityistheabilityofasinglegenotypetoproducedifferentphenotypeswhenexposedtodifferentenvironmentalconditions.Thisphenomenoniswidespreadinnatureandservesasacriticalmechanismfororganismstocopewithspatialandtemporalheterogeneityintheirhabitats.Unlikegeneticadaptation,whichinvolveschangesinallelefrequenciesovergenerations,phenotypicplasticityallowsforrapid,oftenreversible,adjustmentswithinanorganism'slifetime.Thisflexibilitycanbeparticularlyadvantageousinfluctuatingenvironmentswheretheoptimalphenotypechangesunpredictably.Oneofthemostdramaticexamplesofphenotypicplasticityisfoundincertainspeciesofaquaticinvertebrates,suchasthewaterfleaDaphnia.WhenDaphniadetectchemicalsignals,knownaskairomones,releasedbypredatorslikephantommidgelarvae,theyundergosignificantmorphologicalchanges.Thesechangesincludethedevelopmentofelongatedspinesand"helmets"ontheirheads,whichmakethemmoredifficultforthepredatortoingest.Thisinduceddefenseisadirectresponsetotheimmediatethreatofpredation.Crucially,ifthepredatorisremoved,subsequentgenerationsofDaphniawillreverttothetypical,undefendedmorphology,demonstratingthereversiblenatureofthisplasticity.Thephysiologicalmechanismsunderlyingphenotypicplasticityofteninvolvecomplexgeneregulatorynetworks.Environmentalstimulitriggersignaltransductionpathwaysthatleadtochangesingeneexpression.Forinstance,inplants,thephytochromesystemdetectslightqualityandquantity,influencingstemelongation,leafexpansion,andchlorophyllproduction.Aplantgrowninashadedenvironmentwillallocatemoreresourcestoverticalgrowthtoreachsunlight,whereasthesamegenotypegrowninfullsunwilldevelopamorecompact,bushierstructure.Thisdifferentialallocationofresources—termed"shadeavoidance"—isaclassicplasticresponsethatmaximizesphotosyntheticefficiencyandreproductivesuccessundervaryinglightconditions.Whilephenotypicplasticityoffersclearbenefits,itisnotwithoutcosts.Producingandmaintainingthesensoryandphysiologicalmachineryrequiredtodetectenvironmentalcuesandeffectphenotypicchangesconsumesenergy.Furthermore,theinducedphenotypemaybesuboptimaliftheenvironmentalcuewasmisleadingoriftheenvironmentchangesagainrapidly.Forexample,ifapredatorcueinducesthedevelopmentofdefensivespinesinDaphnia,butthepredatorsubsequentlydisappears,theenergyinvestedinspinegrowthcouldhavebeenusedforreproductionorgrowthinstead.This"costofplasticity"suggeststhatplasticityisfavoredbynaturalselectiononlyinenvironmentswherethebenefitsofbeingflexibleoutweightheproductionandmaintenancecosts.Fromanevolutionaryperspective,phenotypicplasticitycaninfluencethetrajectoryofnaturalselection.The"Baldwineffect"proposesthattheabilitytolearnoradaptplasticallycanshieldorganismsfromselectionpressure,allowinggeneticvariationtoaccumulatesilently.Overtime,thisgeneticvariationmighteventuallyleadtothegeneticassimilationofatrait,wherethephenotypebecomesfixedevenintheabsenceoftheoriginalenvironmentaltrigger.Inthisway,plasticitycanactasabridgebetweenindividualflexibilityandevolutionaryadaptation,facilitatingthecolonizationofnewnichesandpotentiallydrivingspeciation.Recentresearchhasalsohighlightedtheroleofepigeneticsinmediatingphenotypicplasticity.Epigeneticmodifications,suchasDNAmethylationandhistonemodification,canaltergeneexpressionwithoutchangingtheunderlyingDNAsequence.Thesemodificationscanbestableacrosscelldivisionsand,insomecases,eventransmittedtooffspring,providingaformoftransgenerationalplasticity.Thissuggeststhatparentalexposuretostresscanprimeoffspringtobetterwithstandsimilarstressors,aphenomenonobservedinplantsexposedtodroughtorherbivory.Suchmechanismsaddalayerofcomplexitytoourunderstandingofheredityandadaptation,blurringthelinebetweengeneticandenvironmentalinfluences.1.Theword"heterogeneity"inthepassageisclosestinmeaningtoA.uniformityB.diversityC.stabilityD.hostility2.Accordingtoparagraph2,whathappenstoDaphniawhenpredatorkairomonesarepresentinthewater?A.Theyincreasetheirabilitytoswimrapidly.B.TheyproducechemicalsignalstowarnotherDaphnia.C.Theydevelopphysicalstructuresthathinderpredation.D.Theyreproducemoreslowlytoconserveenergy.3.Whichofthesentencesbelowbestexpressestheessentialinformationinthefollowingsentence?"Thisdifferentialallocationofresources—termed'shadeavoidance'—isaclassicplasticresponsethatmaximizesphotosyntheticefficiencyandreproductivesuccessundervaryinglightconditions."A.Shadeavoidanceisaplasticresponsewhereplantschangetheirresourceallocationtoimprovereproductionandphotosynthesisbasedonlightavailability.B.Plantsinfullsungrowtallertoavoidshade,whichhelpsthemmaximizetheirreproductivesuccesscomparedtoplantsintheshade.C.Thedifferentialallocationofresourcesisaresponsethatisonlyfoundinplantslivinginenvironmentswithvaryinglightconditions.D.Photosyntheticefficiencyismaximizedbytheshadeavoidancemechanism,whichistheprimarygoalofallplasticresponsesinplants.4.Theword"suboptimal"inthepassageisclosestinmeaningtoA.idealB.secondaryC.lessthanidealD.temporary5.Inparagraph4,theauthormentionsthe"costofplasticity"inordertoA.explainwhyphenotypicplasticityisrareinnature.B.arguethatplasticityisalwaysbeneficialtoorganisms.C.illustratealimitationthatpreventsplasticityfromevolvinginallenvironments.D.provethatgeneticadaptationissuperiortophenotypicplasticity.6.Accordingtoparagraph5,the"Baldwineffect"suggeststhatA.plasticityallowsorganismstoavoidextinction,preventinggeneticvariationfromoccurring.B.geneticassimilationoccursbeforeanorganismcanadaptplasticallytoanewenvironment.C.plasticitycanprotectorganismsfromselection,allowinggeneticvariationtobuildupthatmaylaterbecomefixed.D.individualflexibilityistheonlydriverofspeciationandevolutionarychange.7.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."Thesechangesarenotrandom;rather,theyarefinelytunedadaptationsthatenhancesurvival."Wherewouldthesentencebestfit?A.WhenDaphniadetectchemicalsignals,knownaskairomones,releasedbypredatorslikephantommidgelarvae,theyundergosignificantmorphologicalchanges.[■]B.Thesechangesincludethedevelopmentofelongatedspinesand"helmets"ontheirheads,whichmakethemmoredifficultforthepredatortoingest.[■]C.Thisinduceddefenseisadirectresponsetotheimmediatethreatofpredation.[■]D.Crucially,ifthepredatorisremoved,subsequentgenerationsofDaphniawillreverttothetypical,undefendedmorphology,demonstratingthereversiblenatureofthisplasticity.[■]8.Theword"mediating"inthepassageisclosestinmeaningtoA.causingB.resolvingC.facilitatingD.complicating9.Whichofthefollowingcanbeinferredfromparagraph6aboutepigeneticmodifications?A.TheyarepermanentchangestotheDNAsequenceofanorganism.B.Theycanbepasseddowntothenextgeneration,influencingtheoffspring'sphenotype.C.TheyaretheprimarymechanismbehindtheBaldwineffectonanevolutionaryscale.D.Theyonlyoccurinresponsetodroughtandherbivoryinplants.10.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.Phenotypicplasticityallowsorganismswiththesamegeneticmakeuptodevelopdifferenttraitsinresponsetoenvironmentalchanges.____________A.OrganismslikeDaphniaandplantsexhibitplasticitythroughmorphologicalandphysiologicalchangesthatimprovesurvivalandresourceacquisition.B.Geneticadaptationisafasterprocessthanphenotypicplasticitybecauseitinvolveschangesinallelefrequencies.C.Theevolutionofplasticityisconstrainedbyenergeticcostsandtheriskofproducingtraitsthatarenotsuitedtotheenvironment.D.TheBaldwineffectproposesthatplasticitycanfacilitateevolutionarychangebyallowinggeneticvariationtoaccumulate.E.Epigeneticmechanisms,suchasDNAmethylation,canexplainhowandwhygeneticmutationsoccurinpopulations.F.Unlikeanimals,plantsdonothavecomplexsensorysystemsandthereforecannotexhibitphenotypicplasticity.PassageTwoTheEvolutionofUrbanPlanningintheIndusValleyCivilizationTheIndusValleyCivilization(IVC),flourishingaround2600to1900BCEinwhatisnowmodern-dayPakistanandnorthwestIndia,isrenownedforitsadvancedurbanplanning.Amongitsmostnotablecharacteristicsarethesophisticatedcitylayouts,particularlyevidentinmajorurbancenterslikeMohenjo-DaroandHarappa.UnlikethecontemporarycivilizationsofMesopotamiaandEgypt,whichoftengreworganicallyaroundatempleorpalacecomplex,IndusValleycitieswereconstructedaccordingtoarigid,standardizedgridpattern.Thislevelofplanningsuggeststheexistenceofastrong,centralizedauthoritycapableofmobilizinglaborandresourcesforlarge-scalepublicworks.ThegridsystemoftheInduscitieswasorientedtothecardinaldirections,withmainstreetsrunningnorth-southandeast-west.Theseprimarythoroughfareswereremarkablywide,somemeasuringupto9metersinwidth,whilesmallerlanesbranchedofftoaccessindividualbuildings.Theuniformityoffiredbricksusedinconstructionacrossdifferentcitiesisstriking;thebricksfollowedastandardratioofapproximately4:2:1,whichfacilitatedconstructionandensuredstructuralintegrity.Thisstandardizationimpliesaformofmunicipalgovernancethatenforcedbuildingcodes,aconceptotherwiseunheardofintheancientworld.Thepreciselayoutalsohadpracticalimplications,likelyaidingindrainageandventilationwithinthedenselypopulatedurbancenters.PerhapsthemostimpressiveaspectofIndusValleyurbanismwasitssanitationanddrainagesystems.NearlyeveryhouseinMohenjo-Darowasconnectedtoacovered,undergrounddrainagenetwork.Thehousesthemselveswereoftenbuiltwithbathrooms,andwastewaterfromtheseflowedintothestreetdrains.Thesedrainsweremadeofbakedbrickandwereequippedwithinspectiontrapsandmanholestoallowforcleaningandmaintenance.Thisattentiontopublichygieneindicatesasocietalpriorityonhealthandcleanlinessthatwasmillenniaaheadofitstime.Incontrast,sewagesystemsinEuropeancitiesonlyappearedmuchlaterinhistory.Theprovisionofwatersupplywasequallyadvanced.Archaeologistshavediscoverednumerouswellsthroughoutthecities,oftenlocatedinprivatecourtyardsorpublicspaces,ensuringareliablesourceoffreshwaterfortheinhabitants.Theconstructionofthesewells,linedwithwedge-shapedbrickstopreventcollapse,demonstratesahighdegreeofengineeringskill.Furthermore,the"GreatBath"ofMohenjo-Daro,alarge,water-tightpoolconstructedoffinelyfittedbricksandsealedwithalayerofbitumen,suggeststhatwaterplayedasignificantroleinritualorcommunallife.TheexactfunctionoftheGreatBathremainsdebated,butitscomplexitypointstotheimportanceofwatermanagementbeyondmereutilitarianneeds.Despitethesophisticationoftheirplanning,IndusValleycitieslackedthemonumentalarchitecturetypicalofotherearlycivilizations.TherearenomassivezigguratslikeinUr,orcolossalpyramidslikethoseatGiza.Thelargeststructuresidentified,suchasthegranaryatHarappaorthe"citadel"mounds,werefunctionalratherthanostentatious.Thecitadelareas,raisedonartificialmud-brickplatforms,likelyhousedadministrativeorreligiouselite,buttheydidnotdominatetheskylineinthewaytemplesorpalacesdidelsewhere.ThisabsenceofroyalpropagandathrougharchitecturehasledsomescholarstospeculatethattheIVCmayhavebeenruledbyamerchantoligarchyoratheocracythatdidnotrequiregrandiosestructurestoassertauthority,orperhapsthatpowerwasmorediffuse.ThedeclineoftheIndusValleyCivilizationaround1900BCEremainsasubjectofintenseinvestigation.Astheurbancenterswereabandoned,thesophisticatedplanningandmaintenancesystemscollapsed.Sometheoriesattributethedeclinetoclimatechange,specificallythedryingupoftheGhaggar-Hakrariversystem,whichwouldhavedevastatedtheagriculturalbase.OtherspointtoinvasionsbyIndo-Aryanpeoplesortointernalsocialandeconomicfactors.Regardlessofthecause,theendoftheIVCmarkedthelossofauniqueurbantraditionthatwouldnotbeseenintheIndiansubcontinentformillennia.TheprinciplesofgridplanningandsanitationthatwerehallmarksoftheInduscitiesdisappeared,onlytoberediscoveredandimplementedinthemodernera.11.Theword"mobilizing"inthepassageisclosestinmeaningtoA.gatheringB.transportingC.financingD.motivating12.Accordingtoparagraph2,whichofthefollowingistrueaboutthebricksusedinIndusValleycities?A.Theyweremadeofmudbrickratherthanfiredbrick.B.TheirdimensionsvariedsignificantlybetweenHarappaandMohenjo-Daro.C.Theyfollowedaconsistentratiothathelpedinconstruction.D.Theywereprimarilyusedforreligiousmonumentsratherthanresidentialbuildings.13.WhydoestheauthormentionMesopotamiaandEgyptinparagraph1?A.TohighlighttheuniquenessofthegridsystemfoundintheIndusValley.B.TosuggestthattheIndusValleycivilizationwasolderthantheseothercivilizations.C.Toprovethatallancientcivilizationsreliedoncentralizedauthority.D.Toillustratethetraderoutesthatconnectedthethreeregions.14.Theword"utilitarian"inthepassageisclosestinmeaningtoA.practicalB.religiousC.socialD.artistic15.Accordingtoparagraph5,whatinferencecanbemadeaboutthepoliticalstructureoftheIndusValleyCivilization?A.Itwasruledbyasinglekingwholivedinthegranary.B.Itlackedacentralizedgovernmentduetotheabsenceofpalaces.C.Itmayhavebeenlessfocusedondisplayingpowerthroughlargemonumentsthanothercivilizations.D.Itwasademocracywherecitizensvotedontheconstructionofpublicworks.16.WhichofthefollowingisNOTmentionedinparagraph3asafeatureofthedrainagesysteminMohenjo-Daro?A.Itwascoveredandunderground.B.Itincludedmanholesformaintenance.C.Itwasusedtoirrigateagriculturalfields.D.Itconnectedtoindividualhouses.17.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."Thisengineeringfeatpreventedthecontaminationofdrinkingwatersources."Wherewouldthesentencebestfit?A.NearlyeveryhouseinMohenjo-Darowasconnectedtoacovered,undergrounddrainagenetwork.[■]B.Thehousesthemselveswereoftenbuiltwithbathrooms,andwastewaterfromtheseflowedintothestreetdrains.[■]C.Thesedrainsweremadeofbakedbrickandwereequippedwithinspectiontrapsandmanholestoallowforcleaningandmaintenance.[■]D.Thisattentiontopublichygieneindicatesasocietalpriorityonhealthandcleanlinessthatwasmillenniaaheadofitstime.[■]18.Accordingtoparagraph6,whatisonetheoryregardingthedeclineoftheIndusValleyCivilization?A.AwarwiththeEgyptianempire.B.Thedepletionofbrick-makingresources.C.Environmentalchangesaffectingwatersources.D.Theintroductionoftheplaguebyforeigntraders.19.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.TheIndusValleyCivilizationexhibitedahighlyadvancedlevelofurbanplanningandengineering.____________A.Citieswerebuiltonastandardizedgridpatternwithuniformbuildingmaterials,suggestingstrongcentralgovernance.B.Thecivilizationpossessedsophisticatedsanitationandwatermanagementsystems,includingcovereddrainsandpublicwells.C.Unlikeotherancientcivilizations,theIndusValleylackedmonumentalarchitecture,possiblyindicatingadifferentpoliticalstructure.D.TheGreatBathwasusedprimarilyasareservoirforstoringwaterduringthedryseason.E.Thedeclineofthecivilizationwasdefinitelycausedbyinvasionsfromthenorth,asevidencedbydestroyedcitywalls.F.TheIndusValleypeopletradedextensivelywithChina,bringingsilkandporcelaintotheregion.PassageThreeTheRoleofAlgaeinGlobalCarbonCyclingTheglobalcarboncycleisacomplexsystemofbiological,chemical,andphysicalprocessesbywhichcarbonisexchangedamongthebiosphere,pedosphere,geosphere,hydrosphere,andatmosphere.Whileterrestrialforestsareoftenhighlightedfortheirroleinsequesteringcarbondioxide,marineenvironments,andspecificallyalgae,playanequally,ifnotmore,significantrole.Algae,rangingfrommicroscopicphytoplanktontomassivekelpforests,areresponsibleforapproximately50%ofglobalprimaryproduction.Throughtheprocessofphotosynthesis,theyconvertdissolvedcarbondioxide(C)andwaterintoorganicmatterandoxygen,formingthebaseofthemarinefoodwebandactingasamassivebiologicalpump.Theequationforphotosynthesisinalgaeisfundamentallysimilartothatofterrestrialplants:6However,theefficiencyandscaleofthisprocessintheoceanarestaggering.Phytoplankton,whichdriftneartheocean'ssurface,utilizenutrientssuchasnitrates,phosphates,andirontofueltheirgrowth.Whentheseorganismsdieorareconsumedbyzooplankton,aportionofthecarboncontainedintheircellssinkstothedeepocean.Thisverticalfluxofcarbon,knownasthebiologicalcarbonpump,effectivelyremovescarbonfromtheatmosphereforcenturiestomillennia,isolatingitinthedeep-seasediments.Withoutthispump,atmosphericCconcentrationswouldbesignificantlyhigher,exacerbatingthegreenhouseeffect.Aspecificgroupofalgae,thecoccolithophores,playsauniqueanddualroleinthecarboncycle.Thesephytoplanktonarecoveredinintricateplatesmadeofcalciumcarbonate(CaC)calledcoccoliths.Astheyphotosynthesize,theyconsumeC,buttheformationoftheircalciumcarbonateshellsreleasesCbackintothewater.TheneteffectofcoccolithophoresonatmosphericInrecentdecades,thephenomenonofoceanacidificationhasraisedconcernsaboutthefuturehealthofalgalpopulationsandtheircapacitytoregulatetheclimate.AstheoceanabsorbsanthropogenicCemissions,thepHofseawaterdecreases,makingitmoreacidic.Thischemicalshiftreducestheavailabilityofcarbonateions,whichareessentialbuildingblocksfororganismslikecoccolithophoresandcoralstobuildtheircalciumcarbonatestructures.Experimentshaveshownthatunderacidifiedconditions,coccolithophoresproducemalformedandthinnershells.Thisimpairmentnotonlythreatensthesurvivaloftheseorganismsbutalsorisksweakeningthebiologicalcarbonpump,creatingapositivefeedbackloopthatacceleratesclimatechange.Anothercriticalaspectofalgalinvolvementinthecarboncycleistheirinteractionwiththe"microbialloop."Intheeuphoticzone(thesunlitupperlayeroftheocean),asignificantamountoforganiccarbonproducedbyalgaeisnotconsumedbylargerzooplanktonbutisinsteadtakenupbymarinebacteria.Thesebacteriarespire,convertingorganiccarbonbackintoC,whichisthenreleasedintothesurfacewatersandpotentiallytheatmosphere.Thisprocessrecyclesnutrientswithinthesurfacelayerbutreducestheefficiencyofcarbonexporttothedeepocean.Understandingthebalancebetweencarbonexportviasinkingparticlesandcarbonrecyclingviathemicrobialloopiscrucialforpredictinghowtheocean'scapacitytoabsorbcarbonwillrespondtoglobalchange.Geoengineeringproposalshaveemergedthatseektoenhancethenaturalcarbon-sequesteringabilityofalgae.Oneprominentideais"ironfertilization,"whereironisaddedtonutrient-richbutiron-poorregionsoftheocean(suchastheSouthernOcean)tostimulatemassivephytoplanktonblooms.ThehypothesisisthatthesebloomswilldrawdownCandsubsequentlysinktothedeepocean.However,large-scaleironfertilizationexperimentshaveyieldedmixedresults.Whilebloomsdooccur,muchofthecarbonisoftenrecycledinthesurfacelayerbythemicrobiallooporconsumedbygrazersbeforeitcansink.Moreover,thereareconcernsaboutunintendedecologicalconsequences,suchastheproductionofharmfulgreenhousegaseslikenitrousoxideorthedepletionofoxygenindeepwaters,leadingtohypoxia.20.Theword"sequestering"inthepassageisclosestinmeaningtoA.releasingB.capturingC.measuringD.ignoring21.Accordingtoparagraph2,whatistheprimaryfunctionofthebiologicalcarbonpump?A.Toconvertorganicmatterintooxygeninthesurfacewaters.B.Totransportcarbonfromthesurfaceoceantothedeepoceansediments.C.Torecyclenutrientslikenitratesandphosphatesintheeuphoticzone.D.Topreventtheoceanfrombecomingtooacidic.22.Theauthormentionscoccolithophoresinparagraph3toillustrateA.howalgaecanbothremoveandreleasecarbondioxidethroughdifferentbiologicalprocesses.B.thedangersofoceanacidificationonmarinelife.C.whylimestoneisthemostcommonsedimentaryrockintheocean.D.theefficiencyofphotosynthesisinmarineenvironmentscomparedtolandplants.23.Whichofthefollowingcanbeinferredfromparagraph4aboutoceanacidification?A.Itincreasestheavailabilityofcarbonateionsinthewater.B.Itisprimarilycausedbytherespirationofmarinebacteria.C.Itposesathreattothestabilityoftheglobalcarboncyclebyaffectingalgalcalcification.D.Itbenefitscoccolithophoresbymakingiteasierforthemtobuildshells.24.Theword"impairment"inthepassageisclosestinmeaningtoA.improvementB.adaptationC.damageD.growth25.Accordingtoparagraph5,howdoesthemicrobialloopaffectthecarboncycle?A.Itenhancestheexportofcarbontothedeepocean.B.ItconvertsorganiccarbonintoCinthesurfacewaters,reducingdeep-seacarbonstorage.C.Itpreventsthegrowthofphytoplanktonbyconsumingallavailablenutrients.D.Itistheprimarymechanismbywhichcoccolithophoresformtheirshells.26.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage."Thisprocesseffectivelylocksawaycarbonthatwouldotherwisecontributetoatmosphericwarming."Wherewouldthesentencebestfit?A.Throughtheprocessofphotosynthesis,theyconvertdissolvedcarbondioxide(C)andwaterintoorganicmatterandoxygen,formingthebaseofthemarinefoodwebandactingasamassivebiologicalpump.[■]B.Whentheseorganismsdieorareconsumedbyzooplankton,aportionofthecarboncontainedintheircellssinkstothedeepocean.[■]C.Thisverticalfluxofcarbon,knownasthebiologicalcarbonpump,effectivelyremovescarbonfromtheatmosphereforcenturiestomillennia,isolatingitinthedeep-seasediments.[■]D.Withoutthispump,atmosphericCconcentrationswouldbesignificantlyhigher,exacerbatingthegreenhouseeffect.[■]27.Whatistheauthor'sattitudetowardtheproposalofironfertilizationinparagraph6?A.Hestronglysupportsitasthebestsolutiontoglobalwarming.B.Heisskepticalofitseffectivenessandconcernedaboutitssideeffects.C.Hebelievesitisimpossibletoimplementonalargescale.D.Hesuggeststhatitwillleadtotheextinctionofmostphytoplanktonspecies.28.Directions:Completethetablebelowbymatchingthecorrecttypeofalgaeorprocesswithitsdescriptionoreffect.Thisquestionisworth3points.TypeofAlgae/Process............Description/EffectA.Phytoplankton....................1.Responsiblefortheformationofcalciumcarbonateshells.B.Coccolithophores................2.ConvertsCtoorganicmatter;somecarbonsinkstothedeepocean.C.TheMicrobialLoop...............3.Recyclesorganiccarboninsurfacewaters,reducingcarbonexport................................................4.Consumesironandothernutrientstofuelgrowth................................................5.ReleasesCduringtheformationofitsexternalstructure.A.Phytoplankton:2,4B.Coccolithophores:1,5C.TheMicrobialLoop:3答案与解析PassageOne1.B解析：词汇题。“Heterogeneity”意为“异质性”或“多样性”，指环境的不均匀。文中提到copewithspatialandtemporalheterogeneity（应对空间和时间的异质性），即环境的多样性。Uniformity（统一性）是反义词；Stability（稳定性）和Hostility（敌意）不符合语境。2.C解析：细节题。根据第二段第二句：“WhenDaphniadetectchemicalsignals...theyundergosignificantmorphologicalchanges.Thesechangesincludethedevelopmentofelongatedspinesand'helmets'ontheirheads,whichmakethemmoredifficultforthepredatortoingest.”当检测到捕食者信号时，水蚤会发育出刺和头盔，使其更难被捕食，即阻碍捕食的物理结构。3.A解析：句子简化题。原句意为：这种差异化的资源分配——被称为“避荫”——是一种典型的可塑性反应，它能在变化的光照条件下最大化光合作用效率和繁殖成功率。选项A准确概括了避荫反应、资源分配以及目的（光合作用和繁殖）。选项B提到植物在阳光下长高是错误的（是在阴影下）；选项C过于绝对；选项D忽略了繁殖成功率。4.C解析：词汇题。“Suboptimal”意为“次优的”或“非最佳的”，即不是最理想的。Lessthanideal是同义替换。5.C解析：修辞目的题。第四段讨论了可塑性的成本，包括能量消耗和产生误导性表型的风险。提到“costofplasticity”是为了说明为什么可塑性并不是在所有环境中都会进化出来，因为只有当收益大于成本时，它才会被自然选择青睐。选项C正确。6.C解析：细节题。根据第五段：“The'Baldwineffect'proposesthattheabilitytolearnoradaptplasticallycanshieldorganismsfromselectionpressure,allowinggeneticvariationtoaccumulatesilently.”这表明可塑性可以保护生物免受选择压力，允许遗传变异积累。7.B解析：插入题。待插入句子意为：“这些变化不是随机的；相反，它们是提高生存率的精细调节的适应。”这是对前一句提到的形态变化（elongatedspinesandhelmets）的进一步评价和总结。放在B处，前一句描述了具体的变化，后一句解释了这些变化的功能，逻辑通顺。8.C解析：词汇题。“Mediating”意为“调解”或“促成”，