2026年3月托福真题及答案

2026年3月托福真题及答案第一部分：阅读Passage1TheEvolutionofC4PhotosynthesisPhotosynthesisistheprocessbywhichplantsconvertlightenergyintochemicalenergy,fuelingthebiosphere.ThemostcommonformofphotosynthesisisknownasC3photosynthesis,namedbecausethefirststableproductofcarbonfixationisathree-carbonmolecule(3-phosphoglycerate).However,underconditionsofhightemperature,highlightintensity,anddrought,C3plantssufferfromaprocesscalledphotorespiration.Duringphotorespiration,theenzymeRubiscobindswithoxygeninsteadofcarbondioxide,significantlyreducingtheefficiencyofphotosynthesisandwastingenergy.Toovercomethislimitation,certainplantlineagesevolvedadistinctcarbonfixationmechanismknownasC4photosynthesis.ThismechanismspatiallyseparatestheinitialfixationofcarbondioxidefromtheCalvincycle.InC4plants,carbondioxideisfirstfixedinmesophyllcellstoformafour-carboncompound(oxaloacetate,whichisusuallyconvertedtomalateoraspartate).Thisfour-carbonacidisthentransportedtobundle-sheathcells,whicharetightlywrappedaroundthevascularbundlesoftheleaf.Insidethesebundle-sheathcells,theC4acidisdecarboxylated,releasingahighconcentrationofcarbondioxide.ThiselevatedconcentrationofCsuppressesphotorespirationbyensuringthatRubiscobindsprimarilywithcarbondioxide,evenwhenstomataarepartiallyclosedtoconservewater.TheevolutionofC4photosynthesisisaremarkableexampleofconvergentevolution,havingarisenindependentlyinover60differentplantlineages,includinggrasseslikemaizeandsugarcane,aswellasdicotslikeamaranth.Thisconvergencesuggestsstrongselectivepressure,particularlyduringperiodsoflowatmosphericcarbondioxide.GeologicalrecordsindicatethatatmosphericClevelshavefluctuateddramaticallyoverthelast30millionyears.DuringtheOligoceneandMioceneepochs,adeclineinatmosphericClikelycreatedanenvironmentwhereC3plantswereincreasinglydisadvantaged,therebyfavoringtheemergenceandproliferationofC4species.Anatomically,C4plantspossessauniqueleafstructureknownas"Kranzanatomy."Theterm"Kranz"isGermanfor"wreath,"referringtothering-likearrangementofbundle-sheathcellssurroundingthevascularbundles.ThisstructuralarrangementiscrucialforthefunctionoftheC4pathway,asitminimizesthediffusionofcarbondioxidereleasedinthebundle-sheathcells,maintainingthehighconcentrationnecessaryforefficientCalvincycleactivity.Furthermore,themesophyllcellsinC4plantsareoftenarrangedconcentricallyaroundthebundle-sheath,facilitatingtherapidtransportofmetabolitesbetweenthetwocelltypes.WhileC4photosynthesisrequiresmoreenergyintheformofATPpermoleculeofcarbondioxidefixedcomparedtoC3photosynthesis,theeliminationofphotorespirationresultsinanetgaininefficiencyundertropicalandsubtropicalconditions.Consequently,C4plantsdominateinhot,aridenvironmentsandareamongtheworld'smostproductivecrops,accountingforasignificantportionofglobalprimaryproductivityintheseregions.UnderstandingthebiochemicalandgeneticbasisofC4photosynthesisiscurrentlyamajorfocusofagriculturalresearch,asscientistsexplorethepossibilityofengineeringC4traitsintomajorC3cropslikericeandwheattoenhancetheiryieldandresiliencetoclimatechange.1.Theword"suppresses"inthepassageisclosestinmeaningtoA.inhibitsB.encouragesC.regulatesD.measures2.Accordingtoparagraph2,whyisthespatialseparationofprocessesinC4plantsimportant?A.Itallowstheplanttofixcarbondioxideatnight.B.ItpreventsRubiscofrombindingwithoxygen.C.Itincreasestheamountofwaterstoredintheleaves.D.Itallowstheplanttosurviveinfreezingtemperatures.3.Theauthormentions"maizeandsugarcane"inparagraph3inordertoA.provideexamplesofC3plantsthatarevulnerabletodrought.B.listthemostancientformsofplantlifeonEarth.C.illustratethatC4photosynthesishasevolvedinmultipletypesofplants.D.arguethatthesecropsshouldbereplacedbyC3varieties.4.Accordingtoparagraph3,whatgeologicalfactorcontributedtotheevolutionofC4photosynthesis?A.Anincreaseinglobaloceantemperatures.B.Ariseinatmosphericoxygenlevels.C.Adecreaseinatmosphericcarbondioxidelevels.D.Thefrequencyofmeteoriteimpacts.5.Theword"concentrically"inthepassageisclosestinmeaningtoA.sparselyB.radiallyC.irregularlyD.vertically6.Whichofthesentencesbelowbestexpressestheessentialinformationinthehighlightedsentenceinparagraph5?Incorrectchoiceschangethemeaninginimportantwaysorleaveoutessentialinformation.A.AlthoughC4photosynthesisusesmoreenergy,itismoreefficientthanC3photosynthesisinhot,dryclimatesbecauseitpreventsphotorespiration.B.C4photosynthesisislessefficientthanC3photosynthesisbecauseitrequiresmoreATPtofixcarbondioxide.C.C3photosynthesisissuperiorinallenvironmentsbecauseitrequireslessenergytoproducesugar.D.TheenergycostofC4photosynthesismakesitunsuitableforagriculturaluseintropicalregions.7.Theword"consequently"inthepassageisclosestinmeaningtoA.howeverB.thereforeC.surprisinglyD.previously8.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.ThisstructuraladaptationensuresthattheenzymeRubiscooperatesinaCO2-richenvironment.Wherewouldthesentencebestfit?A.Insidethebundle-sheathcells,theC4acidisdecarboxylated,releasingahighconcentrationofcarbondioxide.[■]B.ThiselevatedconcentrationofCsuppressesphotorespirationbyensuringthatRubiscobindsprimarilywithcarbondioxide,evenwhenstomataarepartiallyclosedtoconservewater.[■]C.TheevolutionofC4photosynthesisisaremarkableexampleofconvergentevolution,havingarisenindependentlyinover60differentplantlineages,includinggrasseslikemaizeandsugarcane,aswellasdicotslikeamaranth.[■]D.Thisconvergencesuggestsstrongselectivepressure,particularlyduringperiodsoflowatmosphericcarbondioxide.[■]9.Directions:Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.CompletethesummarybyselectingtheTHREEanswerchoicesthatexpressthemostimportantideasinthepassage.Somesentencesdonotbelonginthesummarybecausetheyexpressideasthatarenotpresentedinthepassageorareminorideasinthepassage.C4photosynthesisisanevolutionaryadaptationthatenhancescarbonfixationefficiencyunderspecificenvironmentalconditions.A.C3photosynthesisisinefficientinhot,dryclimatesduetophotorespiration,whereRubiscobindswithoxygeninsteadofcarbondioxide.B.C4plantsphysicallyseparatecarbonfixationintomesophyllandbundle-sheathcellstoconcentrateCaroundRubisco.C.TheevolutionofC4photosynthesisoccurredonlyonce,inacommonancestorofmoderngrasses.D.KranzanatomyisaspecializedleafstructurethatsupportsthemetabolicneedsoftheC4pathway.E.C4plantsarelessproductivethanC3plantsandarerarelyusedinmodernagriculture.F.AtmosphericchangesduringtheMioceneepochlikelyprovidedtheselectivepressureforthedevelopmentofC4pathways.Passage2TheEconomicandSocialImpactofthePrintingPressTheinventionofthemovabletypeprintingpressbyJohannesGutenbergaround1440iswidelyregardedasoneofthemostsignificanteventsinhumanhistory.PriortoGutenberg,bookswerecopiedbyhand,alaboriousandexpensiveprocessundertakenbyscribesinmonasteriesorscriptoria.Asaresult,bookswererarecommodities,andliteracywaslargelyconfinedtotheclergyandaverysmalleliteofthenobilityandmerchantclasses.Theprintingpressdismantledthismonopolyonknowledgebydramaticallyreducingthecostandtimerequiredtoproducebooks.Theimmediateeconomicimpactoftheprintingpresswasthecreationofanewindustrycenteredontheproductionandsaleofbooks.PrintshopsemergedinmajorcitiesacrossEurope,firstinGutenberg'snativeMainz,thenrapidlyspreadingtoVenice,Paris,andLondon.Thisindustryrequiredacomplexdivisionoflabor,involvingtypefounders,papermakers,inkmakers,andcompositors.Thedemandforpaper,inparticular,spurredashiftfromparchment(animalskin)topapermadefromrags,leadingtotheexpansionofpapermillsthroughoutEurope.ThisindustrializationofthebooktradelaidearlygroundworkforthecapitaliststructuresthatwouldlaterdefinetheEuropeaneconomy.Socially,theprintingpressfacilitatedthespreadofRenaissancehumanism.Humanistscholars,whoemphasizedthestudyofclassicaltexts,werequicktoutilizethenewtechnologytodisseminatetheirideaswithunprecedentedspeedandaccuracy.Thestandardizationoftextsthatprintingaffordedmeantthatscholarsindifferentregionscouldreferencetheexactsamepagenumbersandwording,fosteringasenseofintellectualcommunityandacceleratingtheexchangeofideas.Thiserodedtheregionalvariationsintextsthathadpreviouslycharacterizedmanuscriptculture.Furthermore,theprintingpressplayedacrucialroleintheProtestantReformation.In1517,MartinLuthernailedhisNinety-fiveThesestothechurchdoorinWittenberg,anactthatmighthaveremainedalocaltheologicaldisputewithouttheaidofthepress.Instead,Luther'sideaswereprintedandcirculatedwidely,ignitingareligiousupheavalthatsplitWesternChristendom.ThepressallowedfortherapidtranslationanddistributionoftheBibleintovernacularlanguages,enablingordinarypeopletoreadscriptureforthemselvesandchallengingtheCatholicChurch'sroleasthesoleinterpreterofreligioustruth.However,thetransitionfrommanuscripttoprintwasnotwithoutitscritics.Somescholarslamentedthelossoftheartisticbeautyofilluminatedmanuscripts,whileothersworriedthatthewidespreadavailabilityofbookswouldleadtoinformationoverloadorthespreadofhereticalandseditiousideas.Establishments,bothreligiousandpolitical,attemptedtocontroltheoutputofpressesthroughcensorshipandthegrantingofprintingprivileges.Despitetheseattemptsatcontrol,thedemocratizationofinformationprovedirreversible,fundamentallyalteringtherelationshipbetweentheindividualandauthority.10.Theword"laborious"inthepassageisclosestinmeaningtoA.difficultandtime-consumingB.profitableC.artisticD.illegal11.Accordingtoparagraph2,whydidthedemandforpaperincreaseaftertheinventionoftheprintingpress?A.Parchmentbecametooexpensivetoproduce.B.Paperwasmoredurablethanparchment.C.Theprintingprocessrequiredalargesupplyofmaterialtoprinton.D.Thegovernmentbannedtheuseofanimalskins.12.Theword"dismantled"inthepassageisclosestinmeaningtoA.builtB.brokedownC.supportedD.ignored13.Accordingtoparagraph3,howdidtheprintingpressaffectRenaissancehumanism?A.Itcausedhumanistscholarstoabandonthestudyofclassicaltexts.B.Itallowedhumanistideastospreadquicklyandstandardizedtextsforeasierreference.C.ItforcedtheChurchtostopsupportinghumanisteducation.D.Itmadebookstooexpensiveformosthumanistscholarstopurchase.14.WhydoestheauthormentionMartinLutherinparagraph4?A.Toprovideanexampleofhowtheprintingpressinfluencedreligioushistory.B.TocriticizetheCatholicChurch'sresponsetonewtechnology.C.ToillustratetheartisticqualityofearlyprintedBibles.D.ToarguethatLutherinventedtheprintingpress.15.Accordingtoparagraph5,whatwasonenegativereactiontotheprintingpress?A.Fearthatitwouldspreaddangerousideasandruintheaestheticqualityofbooks.B.Concernthatitwouldcauseunemploymentamongscribes.C.Beliefthatitwouldmakepapertooexpensive.D.Worrythatitwouldstoppeoplefromlearningtoread.16.Lookatthefoursquares[■]thatindicatewherethefollowingsentencecouldbeaddedtothepassage.Thisshiftnotonlyloweredcostsbutalsoincreasedthevolumeofreadingmaterialavailable.Wherewouldthesentencebestfit?A.PriortoGutenberg,bookswerecopiedbyhand,alaboriousandexpensiveprocessundertakenbyscribesinmonasteriesorscriptoria.[■]B.Asaresult,bookswererarecommodities,andliteracywaslargelyconfinedtotheclergyandaverysmalleliteofthenobilityandmerchantclasses.[■]C.Theprintingpressdismantledthismonopolyonknowledgebydramaticallyreducingthecostandtimerequiredtoproducebooks.[■]D.Theimmediateeconomicimpactoftheprintingpresswasthecreationofanewindustrycenteredontheproductionandsaleofbooks.[■]17.Directions:Selecttheappropriatephrasesfromtheanswerchoicesandmatchthemtothecategorytowhichtheyrefer.TWOoftheanswerchoiceswillNOTbeused.AnswerChoices:A.EnabledtherapidspreadofProtestantideas.B.Requiredtheworkofscribesandmonks.C.Createdaneedforpapermills.D.Ledtothecompletedisappearanceofliteracy.E.Standardizedtextsforscholarlyreference.F.Wasstrictlycontrolledbythegovernment.EconomicImpactSocialandReligiousImpactPassage3Earth’sInternalHeatandPlateTectonicsThetheoryofplatetectonics,whichprovidestheframeworkforunderstandingEarth'sdynamicgeology,isfundamentallydrivenbytheplanet'sinternalheat.Earth'sinternalheatoriginatesprimarilyfromtwosources:primordialheatleftoverfromtheplanet'sformationandradioactivedecayofisotopessuchasuranium,thorium,andpotassium.ThisheatenergyistrappedwithintheEarth,creatingathermalgradientthatdrivestheconvectionofthemantle—thelayerofsilicaterockthatliesbetweenthecrustandthecore.Mantleconvectionactsastheengineofplatetectonics.Althoughthemantleissolidrock,itbehaveslikeahighlyviscousfluidovergeologicaltimescalesduetotheintensetemperaturesandpressuresitexperiences.Hottermaterialnearthecore-mantleboundarybecomeslessdenseandslowlyrisestowardthesurface,whilecoolermaterialnearthelithospherebecomesdenserandsinks.Thisslow,circularmotionofmantlematerialcreatesconvectioncells.Thefrictionanddragexertedbythesemovingconvectioncellsontheoverlyinglithosphere(therigidoutershellcomprisingthecrustanduppermostmantle)causethelithosphericplatestomove.Therearethreemaintypesofplateboundaries,eachcharacterizedbydistinctgeologicalphenomenadrivenbythisinternalheat.Divergentboundariesoccurwhereplatesmoveapart,allowinghotmagmafromtheunderlyingmantletoriseandfillthegap,creatingnewcrust.Thisprocessismostevidentalongmid-oceanridges,wheretheupwellingofmantlematerialdrivesseafloorspreading.Conversely,convergentboundariesoccurwhereplatescollide.Here,thedenseroceanicplateistypicallyforcedbeneaththelessdensecontinentalplateinaprocesscalledsubduction.Asthesubductingplatesinksintothemantle,itmeltsduetotheincreasingtemperatureandpressure,generatingmagmathatcanrisetoformvolcanicarcs,suchastheRingofFirecirclingthePacificOcean.Transformboundaries,thethirdtype,occurwhereplatesslidehorizontallypastoneanother.Whilenonewcrustiscreatedordestroyedattheseboundaries,thefrictionbetweentheplatescanlocktheminplaceuntilstressbuildsupsufficientlytocauseasuddenslip,resultinginearthquakes.TheSanAndreasFaultinCaliforniaisafamousexampleofatransformboundary.Themovementalongtheseboundariesisalsoadirectconsequenceofthelateralflowofmantleconvectioncellsbelow.ThereleaseofEarth'sinternalheatisnotuniformacrosstheplanet."Hotspots"areareasoflocalized,intensevolcanismthatarenotnecessarilyassociatedwithplateboundaries.Thesearethoughttobecausedbymantleplumes—narrowstreamsofhotmaterialrisingfromdeepwithinthemantle,possiblyfromthecore-mantleboundary.Asatectonicplatemovesoverastationaryhotspot,achainofvolcanoesisformed,suchastheHawaiianIslands.ThepresenceofhotspotsprovidescrucialevidencefortheinternalthermaldynamicsoftheEarth,suggestingthatheattransportoccursviabothbroadconvectioncellsandfocusedplumes.18.Theword"framework"inthepassageisclosestinmeaningtoA.problemB.structureC.historyD.error19.Accordingtoparagraph1,whatarethetwomainsourcesofEarth'sinternalheat?A.Solarradiationandgeothermalenergy.B.Primordialheatandradioactivedecay.C.Volcaniceruptionsandoceancurrents.D.Frictionbetweenplatesandwindenergy.20.TheauthorstatesthatthemantlebehaveslikeaviscousfluidinordertoexplainA.whythemantleiscomposedofliquidrock.B.howconvectioncellscanmovesolidrockovertime.C.whyearthquakesoccuratthesurface.D.howthecoregeneratesamagneticfield.21.Theword"intense"inthepassageisclosestinmeaningtoA.moderateB.extremeC.variableD.visible22.Accordingtoparagraph3,whathappensataconvergentboundary?A.Magmarisestocreatenewoceaniccrust.B.Platesslidepasteachotherhorizontally.C.Oneplateisforcedbeneathanother,oftenleadingtovolcanism.D.Thelithospherecoolsandsinks.23.HowaretheHawaiianIslandsexplainedinparagraph5?A.TheyaretheresultofatransformboundaryslidingpasttheNorthAmericanPlate.B.Theyformedasaplatemovedoverastationarymantleplume.C.Theyaretheremnantsofamassivemeteoriteimpact.D.TheyareevidenceofadivergentboundaryinthemiddleofthePacificOcean.24.Whichofthefollowingcanbeinferredaboutmantleconvectioncellsfromparagraph5?A.Theyaretheonlymechanismresponsibleformovingtectonicplates.B.Theyoperateatamuchfasterratethanmantleplumes.C.Theymaybesupplementedbymantleplumesintransportingheat.D.Theyareresponsiblefortheformationofallearthquakes.25.Directions:Completethetablebelowbymatchingthephraseswiththetypeofplateboundary.TWOofthephraseswillNOTbeused.TypeofBoundaryDivergentBoundaryConvergentBoundaryTransformBoundaryPhrases:A.CreationofavolcanicarcB.SeafloorspreadingC.HorizontalslidingofplatesD.RisingofmantleplumesE.FormationofnewcrustF.Subductionofoceanicplates第二部分：听力Conversation1Professor:Hi,Sarah,youwantedtoseemeaboutyourtermpaper?Student:Yes,ProfessorMiller.I’mplanningtowriteabouttheimpactofurbangreenspacesonmentalhealth.ButI’mhavingtroublenarrowingdownthefocus.Professor:That’saveryrelevanttopic.It'squitebroad,though.Youcouldlookatitfromvariousangles:socioeconomicfactors,specifictypesofgreenspaces,orperhapsspecificdemographics.Student:Right.Iwasthinkingmaybefocusingoncommunitygardensinlow-incomeneighborhoods.Professor:Thatsoundspromising.There’sexistingresearchonhowcommunitygardensfostersocialcohesion,whichindirectlybenefitsmentalhealth.Butyouneedtomakesureyoufindempiricalstudies,notjustanecdotalevidence.Student:IfoundastudyfromChicagothatshowedareductionincrimeratesnearcommunitygardens.Doesthatcount?Professor:Itrelates,butcrimereductionisabitdistinctfromindividualmentalhealth,thoughthetwoarelinked.I’dsuggestlookingforstudiesthatmeasurecortisollevelsorself-reportedstresslevelsinresidentsbeforeandafterthegardenswereestablished.Student:Cortisollevels...okay,thatsoundsmorescientific.I'llcheckthedatabaseforthat.Professor:Also,considerthe"biophiliahypothesis."Itsuggeststhathumanshaveaninnateconnectiontonature.Youcouldframeyourpaperaroundhowcommunitygardenssatisfythatbiologicalneedinurbandeserts.Student:That’sagreattheoreticalframework.Thanks,Professor.I’llrefinemythesisstatementtoincludethat.1.Whatisthemaintopicoftheconversation?A.Thestudent'sdifficultyinfindingsourcesforherbiologypaper.B.Thestudent'srequestforanextensiononhertermpaper.C.Narrowingdownthetopicofapaperonurbangreenspaces.D.DiscussingtheresultsofastudyoncrimeratesinChicago.2.Whatdoestheprofessorsuggestthestudentfocusonregardingcommunitygardens?A.Theeconomicbenefitsofgrowingfood.B.Thetypesofplantsgrownindifferentclimates.C.Thereductionofcrimeratesinthearea.D.Empiricalstudiesonstresslevelsorsocialcohesion.3.Whydoestheprofessormentionthe"biophiliahypothesis"?A.Tosuggestatheoreticalbasisforthestudent'spaper.B.Tocontradictthestudent'sinitialresearchfindings.C.Toexplainwhysomepeopledislikegardening.D.Torecommendaspecificbookforthestudenttoread.4.Whatdoestheprofessorimplyaboutthestudyoncrimerates?A.Itisnotrelevanttothestudent'stopic.B.Itisusefulbutfocusesonadifferentaspectthanmentalhealth.C.Itwaspoorlyconductedandshouldnotbecited.D.Itisthebeststudythestudenthasfoundsofar.5.Whatwillthestudentlikelydonext?A.Changehertopiccompletelytosomethingaboutbiology.B.Searchforstudiesmeasuringcortisollevels.C.Interviewresidentsinherownneighborhood.D.Writethefirstdraftofherpaperimmediately.Lecture1Professor:Todaywe'regoingtodiscusstheconceptof"carryingcapacity"inecology.Carryingcapacity,usuallydenotedbytheletterKinecologicalformulas,isthemaximumpopulationsizeofaspeciesthatanenvironmentcansustainindefinitely,giventheavailableresourceslikefood,water,andhabitat.Therearetwoprimarymodelspopulationecologistsusetodescribehowpopulationsgrow.Thefirstisexponentialgrowth,oftenrepresentedbytheJ-curve.Thisoccurswhenresourcesareunlimited.Thepopulationgrowslargerandfasterwitheachpassinggeneration.However,intherealworld,resourcesareneverunlimited.Thisbringsustothesecondmodel:logisticgrowth.LogisticgrowthisrepresentedbytheS-curve.Initially,thepopulationgrowsexponentially,butasitapproachestheenvironment'scarryingcapacity,growthrateslowsdown.Why?Becauseofdensity-dependentfactors.Thesearefactorsthatintensifyaspopulationdensityincreases.Competitionforfoodbecomesfierce,diseasespreadsmoreeasilyincrowdedconditions,andpredationmightincrease.Themathematicalformulaforlogisticgrowthis:=Here,ristheintrinsicrateofincrease,Nisthecurrentpopulationsize,andKisthecarryingcapacity.Noticetheterm(1−N/K).AsNgetsclosertoHowever,carryingcapacityisnotafixednumber.Itcanfluctuate.Forexample,aparticularlydryyearmightlowertheamountofvegetation,therebyloweringthecarryingcapacityforherbivores.Conversely,humaninterventioncanartificiallyraisethecarryingcapacityforaspecies,likeagricultureforhumans,orsupplementalfeedingfordeer.It'salsoimportanttonotethatsomepopulationsdonotstabilizesmoothlyatK.Theymightovershootthecarryingcapacityandthencrash.Thisisoftenseeninspecieswithsimplereproductivestrategies,likelemmingsorcertaininsects.Thisboom-and-bustcyclehappensbecausethereisatimelagbetweenthepopulationconsumingresourcesandtherealizationthatthoseresourcesaredepleted.6.Whatisthemainpurposeofthelecture?A.Tocompareexponentialgrowthandlogisticgrowthmodels.B.Toexplaintheconceptofcarryingcapacityandfactorsaffectingit.C.Tocriticizetheuseofmathematicalformulasinecology.D.Todiscussthereproductivestrategiesofinsects.7.Accordingtotheprofessor,whatcausesthegrowthratetoslowdowninlogisticgrowth?A.Adecreaseinthebirthrateduetoagingpopulation.B.Density-dependentfactorslikecompetitionanddisease.C.Humaninterventionintheenvironment.D.Themigrationofanimalstonewareas.8.Whydoestheprofessorwritetheformulaontheboard?A.Toshowthestudentshowtocalculatetheexactnumberofanimalsinaforest.B.TodemonstratemathematicallywhygrowthstopsasNapproachesK.C.Toprovethatexponentialgrowthisimpossibleinnature.D.Toconfusethestudentswithcomplexcalculus.9.Whatdoestheprofessorimplyaboutcarryingcapacity?A.Itisaconstantvalueforanygivenenvironment.B.Itcanchangeduetoenvironmentalvariationsorhumanactivity.C.Itisalwayshigherforpredatorsthanforprey.D.Itisdeterminedsolelybytheamountofwateravailable.10.Whatexampledoestheprofessorgivetoillustrateaboom-and-bustcycle?A.Deerinaforestwithsupplementalfeeding.B.Lemmingsorinsectsthatovershoottheirresources.C.Humanpopulationgrowthduringtheindustrialrevolution.D.Adroughtaffectingapopulationofherbivores.Lecture2Professor:Inarthistory,weoftentalkaboutmovements,buttodayIwanttofocusonaspecifictechniquethatrevolutionizedpainting:Impressionism.BeforetheImpressionists,artwaslargelygovernedbytheAcadémiedesBeaux-ArtsinParis.Theyfavoredrealisticsubjects,smoothbrushstrokesthatwereinvisible,anddark,sombertones.Thepaintingsweremeanttolooklikepolishedwindowsintoreality.TheImpressionists,whoemergedinthelate19thcentury,rejectedthis.Theywantedtocapturethefleetingmoment,theimpressionofascene,specificallythechangingqualityoflight.Oneofthekeytechniquestheydevelopedwas"enpleinair"painting,orpaintingoutdoors.Previously,sketchesmightbedoneoutside,butthefinalpaintingwascompletedinastudio.Bysettinguptheireaselsoutside,Monet,Renoir,andPissarrocouldobservethesky,water,andfoliagedirectly.Thisledtoadrasticchangeintheiruseofcolor.Theyrealizedthatshadowsarenotblack.Infact,shadowsarecoloredbytheobjectcastingthemandthesurroundinglight.Ifyoulookatashadowonsnow,it’slikelyblue,reflectingthesky.TheImpressionistsusedshort,brokenbrushstrokes.Whenviewedupclose,thepaintinglookslikeamessyjumbleofcolors.Butwhenviewedfromadistance,theeyeopticallymixesthesecolors,creatingavibrantluminositythattraditionalblendingcouldn'tachieve.Let'stakeClaudeMonet'sseriesof"Haystacks"asanexample.Hepaintedthesamehaystacksoverandoveragain,butatdifferenttimesofdayanddifferentseasons.Inone,thehaystackisbathedinthewarmorangelightofsunset.Inanother,it’scoveredinsnowunderagreywintersky.Hewasn'tpaintingthehaystackitself;hewaspaintingthelightandatmospheresurroundingit.Thiswasradical.It