其他-这次托福

有了第一次考托的经验，我备考的时候就主攻写作和。像什么"Currently,theissueofwhetherornot..."，直接就拿来用了。第二次的时候就学聪明了，独立写作方面，仔细学习了OG的3/4/5和别人的范4b、别人的文章，比如王子睿的范可以拿来看看，看看他是怎么开头的，以及文章段落内和段落间的衔看网上的经验，觉得自己之前有两个不足：一是原文太多；而是的内容有遗漏。原文多那就只能从拓展词汇量入手了，这个我也没太注意，就是尽量别老是重复使用同个词吧。内容的话可以和部分一起练，后面有讲 31211-MutualisticListentopartofalectureinabiologyProfessor.OK.Sofarwe'vebeenstudyinginteractionsofpopulationsinnaturethatbelongtoacategoryofnegative.Um...we'vediscussedpredatorsthatfeedontheprey,likewolfandrabbit,comrootwormsthatfeedonthecomandsoforth.Thistypeofrelationshipischaracterizedbythefactthatone anismactuallyharmstheother.TodayIwannabegintalkingaboutsomepositiveinteractions. ofall,let'slookatmutualismandtheclassicmutualisticrelationship.Amutualisticrelationshipiswhentwo anismsofdifferentspecies“worktogether,”eachbenefitingfromtherelationshipanddonotharmeachother.Somemutualismsaresoclosethatinteractingspeciesactuallycan'tsurvivewithouteachother.Onegoodexampleofthisisthemutualisticrelationshipbetweentheyuccaplantandyuccamoth,whichyoureadaboutinyourtextbookfortoday.Tom,whyisitthatyuccaplantcan'tlivewithouttheyuccamoth?Tom'Well,itneedstheyuccamothasapollinator,right?Um...theyuccamothcollectsandcarriesthepollenfromoneflowertoanotherindifferentareas.Theyuccaplantwillproduceseedsthatgetcarriedoffbythewindandeventuallygerminateandgrowintonewplantsagain.Professor.Great.Andinterestingly,onlytheyuccamothcanpollinatetheyuccaplant.Mostpeoplethinkofbeeswhentheytalkaboutapollinator.Butevenbeescan'tpollinatetheyuccaplantbecausetheycan'tmovetheyuccapollen.Yuccapollenisreallyheavyandsticky,soitcan'tbescatteredbywindorbycasualcontactwithotherinsects.Buttheyuccamothhasspecialmouthpartsthatenableittocarrythepollen.Uh...Jennifer?Whycan'ttheyuccamothlivewithouttheyuccaplant?Jennifer.Well,whatthefemaleyuccamothdoesis...um...whenshepollinatestheyuccaplant,shealsolayshereggs.Andthen,whentheeggshatch,thelarvaefeedontheyuccaplant'sseeds.Theycan'teatanyotherkindoffood.Imean,theywilldiefromhungerunlesstheyeattheyuccaProfessor.Verygood!So,thisistheperfectkindofrelationship.Theyuccamothpollinatestheyuccaplant,theyuccaplantsmakeseeds,andinreturn,theyuccamothgetsfoodforitsyoungfromtheyuccaplant.Torn:Excuseme,professor.Um,Iseemtobemissingsomethinghere.Imean,Ithoughtyousaid,inmutualism,neitherspeciesisharmed.Buttheyuccamothlarvaeeattheyuccaplant'sseeds.Doesn'tthatmeantheyuccamothactuallyharmstheyuccaProfessor.That'sagoodquestion,Tom.Actuallyit'snotthatmuchofaproblembecausethere'replentyofseedsforthelarvaetoeatwithoutharmingtheyuccaplantsupply.Also,theyuccamothdoesn'tlaytoomanyeggsononeflower.Sheusuallylaysabout1to3perflower.Somostoftheseedswillstillbesafewhentheeggshatch.Butitraisesaninterestingquestion.Whatifafemaleyuccamothplaysunfair?Whatifsheplaysanunfairgameandlaysmoreeggsoneachyuccaflowerthantheusualonetothree.Themothwouldcertainlybebenefitedthiswaybecausemoreoffspringcouldbeproduced.Butitwouldn'tbeverygoodfortheplant.Well,onescientisthasobservedthattheyuccaplantproducesahugearrayofflowersandthendropsalargenumberofflowersincludingmanythathavebeenpollinatedandhaveeggsonthem.Thisdropofflowersisamatterofpurechance.Uh...youneverknowwhichflowerswillfalloff.So,iftheyuccamothlayslotsofeggsatafewflowers,thoseeggsmayallbedropped,andshemayproducenoyoungatall.Butiftheyuccamothlaysfewereggsonlotsandlotsofflowers,there'sagreaterchancethatmorecaterpillarswillhatchandsurviveamongtheflowersthathaveremainedontheplant.Accordingtotheobservation,perhapstheyuccaplantisinasenseforcingthemothtolayeggsthinandwide.17-Tidal21-Faded75=83=7-TheUseofPlantProtein76=86=5-RiverChange78=15=85-Colonizingthe82=15-ColonizingtheMoon83=7-TheUseofPlantProtein84=3-Cézanne85=105=4-IceMaking86=5-River87=33-FlotsamListentopartofalectureinanEarthscienceOK.Beforewefinishclass,I'dliketobrieflytalkaboutsomethingelse.Hasanyoneeverheardofsomethingcalledflotsam废料;浮货;science?No?I'mnotsurprised.aa ethod,butoneofthemoreunusualonesoutthere. Now,flotsam,ofcourse,referstocargoorrecordsfromshipthatfloatingtobewasheduponshore.Flotsamsciencebeganquiteaccidentallysomeyearsago,whenashipmentofplasticbathtoys,shdlike,ducksandturtlesfelloffacargoshipintothePacificOceaninstormyweather.Noonethoughttoomuchaboutthis,ithappensallthetime.Butthenthesetoysstartedtowashupontobeaches,thousandsofaway. Scientistswhotrackoceancurrentswereexciting,sincetheyknewwhenandwherethathadoccurred,theyrealizetheycouldtracetheroutesthesetoyswouldhavetakeniftheyfloatedthroughthePacific.Soflotsamscienceis,generallyspeaking,thescienceoffloatingjunk.Butthisislegitimate合法的，合理的;ifperhapsunconventionalscientificdiscipline这也许是正统的，也许是非传统的科学学科.Infact,thankstoflotsamscienceandthesetravellingbathtoysandotherharmlessstuffthatdroppedoffshipslikeathleticshoes,sportsequipment,younameit.Scientistsnowknowalotmorethantheyusedto,aboutthecurrentsinthenorthernPacific.Thatinformation,inturn,hasallowedscientiststoidentifylongtermchangesinwatertemperatureandsalinitytheamountofsaltinthewaterinthesecurrents.（3结果）Beforeflotsamscience,scientistshavebeentryingtodeterminetheseinformationforyearsbyusingexpensivescientificdevicesthattheywouldsetadriftintheocean.Butthereareproblemswiththesedevices.Foronethingtheyneedtotravelagreatdepthasmuchastwokilometersdownbecauseiftheyrideonthesurfaceoftheocean,theirsensescouldbeobstructedbyalgae,otheranismthatthriveinthesun-litportion 照亮的部分oftheocean.（4问题的具体Butiftheytravelwaybelowthesurfacetoavoidtheseobstructionswelltheydon'tlyoumuchaboutsurfacemovementofthewater,whichiswhatwewanttoknow.Anotherproblemisthatthebatteriesdon'tlastlongenoughtorecordthesophisticateddata,butbathtoys,athleticshoes,thatsortofthing,theytravelonthesurface,andtheydon'tneedbatteriesAndalotofmerchandisethatfallsoffships,likeathleticshoeshavemanufacturingcodesonthemthescientistsuseintracingtheoriginoftheseobjects,andkeetrackoftheirmovements.Andnow,scientistsareusingflotsamscienceformorethanstudyingoceancurrents.Forexample,somescientistsaretryingtouseflotsamsciencetostudyglacialmeltwater.Inthewarmersummermonth,icefromthetoplayerofglaciermelts,formingpoolsofmeltwater.Sofar,it'sbeenachallengetodeterminejusthowmuchiceoftheglaciermeltsinthesummerorwherethemeltwaterendsupbecauseittravelsthroughmoulins冰臼.Amoulinisagiantcrackintheglacierthatmeltwaterdrainsthroughandoncemeltwaterentersthemoulin,itisextremelydifficulttotrack.OnescientistsetouttodeterminewheremeltwaterfromaglacierinGreenlandendsup.Itwasintheneighboringbodyofwater！SowhatdidscientistsdidistosetaspecialscientificinstrumentequippedwithatrackingdevicedownthemoulininGreenland'slargestglacier.Unfortunay,thisratherexpensivedevicedisappeared.OK,sowhasecouldbeused?Nowyouhavetorealizethatconditionsinsidethemoulinsareintenseit'sfreezingcoldplusthere'sahighpressurefromthewayofallthaticeabove.Sowhatwasneedwassomethingreallydurable.HefinallydecidedtouseyellowrubberduckachildrenbathtoyTheiradvantagebeingthemostcheapandstandhighpressureandlowtemperature.Well,afterprintinghisaddress,(5优点)andofferarewardinthreedifferentlanguagesontheduck,hedropped90ofthemdownthemoulinhewasresearching.Nowhehasn'tactuallyhadanyoftheseducksreturnedyet,butheremainshopefulthatsomeonewillfindtheduckandreturntohim.WhatisthelecturemainlyUnusualfeaturesofmeltingEffectsofoceancurrentsonglacierAnunconventionalresearAnenvironmentalproblemcausedbylargeWhydoestheprofessormentionanincidentinvolvingacargoshipinthePacificTopointoutthemainweaknessofflotsamToexplaintheoriginsofflotsamToemphasizetheongoingneedforflotsamToprovideanexampleofhowflotsamsciencebenefitsAccordingtotheprofessor，whatwerescientistsabletoidentifyinPacificOceancurrentsasaresultofflotsamscienceLong-termchangesintemperatureandsaltFluctuationsinthegrowthofTherelationshipbetweenoceandepthandwaterHowwindsaffectwaterspeedandWhydoestheprofessormentionanismsthatthriveintheupperportionsoftheTocontrastglacialmeltwaterwithoceanTodiscussalimitationofacertaintypeofscientificToindicateanewresearchareatowhichflotsamsciencecanToprovideanexampleofhowoceancurrentsaffectwaterWhyhasonescientistusedtoyduckstostudymoulinsClickon2TheycanwithstandcoldtemperaturesandhighTheydonotharmtheTheycanbeeasilyequippedwithelectronicmeasuringTheyareveryWhydoestheprofessorsaythis:OnescientistsetouttodeterminewheremeltwaterfromaglacierinGreenlandendsup.Itwasintheneighboringbodyofwater！一位科学家着手确定格Toindicatetheresearcher'sthoughtToexpresssurpriseat eofanToadmittonotknowinghowtoanswertheresearcher'sToquestionaflawedassumptionmadebytheresearcherCBABADBInourstudiesofimpressionism,we'vealreadyseenhowtheoutdoors..em…howoutdoorsettingsandnaturalsubjectsfigureprominently突出体现inEuropeanimpressionist印象派画paintingsofthe19thcentury.Natureandnaturallandscswerekeytotheartist'snewresourceoflightandcolorwhichplacesanemphasisontheartist'simpressionswhattheartistactuallysawindifferentlightconditionsratherthanonidealizedofplacesandscenes.强调艺术家的印象，艺术家在不同的光照条件下所看到ButthesearetheonlysubjectsweseeinthepaintingsofChildHasomeHasomewasoneofthemostimportantimpressionistpaintersintheUnitedStates.Hewasuniquefor…em…hisbodyofworkrepresentsareallyinterestingdichotomyofbothruralandurbanelements.Nowdon'tgetmewrong,likethebestmajorityofimpressionistsHasomedidpaintmanyruraloutdoorthings.ButthecityespeciallyNewYorkcitywereintomanyofhisworktoo.Yousee,imagineimpressionismdevelopedduringtheindustrialage,averydynamictimeinUShistory,thelate1800s,early1900s.Everythingwaschanging,howpeoplelive,wheretheylive,theirjob.Increasingnumbersofpeoplefromthroughouttheworldimmigratedheretofillthenewfactoryjobandnaturallytheyflockedtothebigcitieswherethosejobswere.Sothecitiesgrewverynoisyandcrowded.Mostoftheearlyimpressionistsreactedto（2-艺术家的反映）thisbyusinganarttocounterthebusyurbanenvironment.Incontrast,allthesechangeandcommersion,theirpaintingsemphasisnature,peace,andpermanent.ManyoftheseartistsmaintainstudiosinNewYorkcityorBoston,buttheyweresummoned召唤;inthecountryside.Andthesespotswereidealfortheiropen-airstylepainting,paintingoutsidewithnaturallighting.Hasomespentmostofhissummeronupperdoorisland.Upperdoorislandwasapopularvacationspotoftheeastcoast.Sopopularitgotalmostascrowdedasacity.Yet,Hasome'supperdoorpaintingsemphasissolitude,aretreatfromurbanlife.（3）Weseeflowers,theoceanareinhivitableluckyquizwithhumansubjectslargelyabsentwhichisartconsideringhowitmighthavebeensurroundedbypeople.Becausebackinthecity,Hasomedidfocusonpeople,hispaintingsofcitylifeorrealisticstudiesoftherelationshipbetweenpeopleandthecity.ThegreatestexamplesareseriesofpaintingsmadeinhisNewYorkcitystudio.Let'shavealookatonepiecefromthatseries,thebreakfastroomwentthroughmorning.Asyoucansee,thebreakfastroomisdistinctivelyurban,itdoesn'thidethecity.Youcanmakeupthetracesoftallbuilding,theflatironbuilding,oneofNewYorkskyscrrandthemajorfeatureofthecityskyline,uhn…,whenthispaintingwasmade.Infact,theflatironbuildingwasconsideredasymbolofmodernrise.SoitsinclusioninthisquietdomesticsceneissignificantIthinkevenmoresignificantishowHasomeandwhere.NoticeonHasometiestheinteriorandexteriorelementstogether.,thereisanimpliedtriangleformedbythewomanontheleft,theflatironbuildinginthecentreandtheboweloffruitontheright,threecorners.（4-1特点）Bystructuringthesceneinthisway,HasomelinksthewomanandherimmediateenvironmenttothecityscbehindherEmm…thesamethingwithcolor（4-2停顿，特点）theblueinthewoman'sdressisechoedintheflatironbuilding,andintheflowers,it'sthesameyellowasthebuildingisattheextremelight.Thisuseofcolormakesyoureyeautomaticallylinkdis…elementstogether.Yet,wellthecityisvisible,isalsocontrolled.Thebuildingsandskylinearewithnudedcoolcolorswhilethewoman'sinwardglanceandwindowskeepthefocusinsidetheroom,creatingaseparationfromthebustlingcityoutside.SoHasomeiseconologyingthechangesofmodernitybyincorporatingthecityintoaquietdomesticscenebutheobscuretheflatironbuildingbehindthecurtain.Infact,thewholecityscismurky,suggestingthatisthepresenceofpeople's allivesortobelimited.Heisprobablyexpressinghisownideasabouthowsocietyshouldrelatetothisnew.Indeedthetheoriesofpaintingswasdirectlyresponsetohisexperienceofurbangrowthandallthatissymbolized.Hecouldn'thavepaintedthebreakfastroomintheruralmid-west.Itwouldn'thavebeenthesamepainting.Thenudedcityhasasourceofinspiration.WhatisthelecturemainlyaboutClickon2Hassam'sinfluenceonartistswhoimmigratedtotheUnitedImpressionistpaintersintheUnitedStatesAcriticalperiodinHassamrisetoprominenceasanImpressionistRelationshipsbetweentheelements（breakfastroom那幅画）insomeofHassam'spaintingswhatdoestheprofessorimplywhenhediscussestheIndustrialManyEuropeanImpressionistsimmigratedtotheUnitedStatesduringthisGrowingpopulationsincitiesledtoanincreasedconsumerdemandforU.S.ImpressionistswantedtheirpaintingstoofferrelieffromcertainaspectsofcityManyU.S.Impressionistspermanentlymovedtothecountrysidewhenthecitiesgotwhatistheprofessor'sattituderegardingthepaintingsthatHassammadeonAppledoreHethinkstheyaremoreinterestingthanHassamewYorkCityHeissurprised（crowdedsolitude）thattheydonotincludemoreHeisimpressedbyhowmanyofthemthereHedoubtsthattheywereactuallypaintedAccordingtotheprofessor,howdoesHassamunitetheimagesinhispaintingTheBreakfastRoom,WinterMorningClickon2answers.ByplacingthemtosuggestthepresenceofageometricByreflectingsunlightoffofinteriorByincludingnaturalobjectsfromtheoutdoorsinanindoorBystrategicallyrepeatingtheuseofcertainAccordingtotheprofessorwhatideadoesHassamsuggestbyobscuringtheFlatironBuildingbehindacurtaininTheBreakfastRoom，WinterMorning用排除法！！！Theneedtocontroltheextenttowhiodernityinvadespeople'sThedifficultyofmaintainingasenseofpermanenceinachangingwhatdoestheprofessormeanwhenhesaysthis“Indeedthetheoriesofpaintingswasdirectlyresponsetohisexperienceofurbangrowthandallthatissymbolized.Hecouldn'thavepaintedthebreakfastroomintheruralmidwest.Itwouldn'thavebeenthesamepainting.Thenudedcityhasasourceofinspiration.-Hecouldn'thavepaintedthebreakfastroomintheruralmidwest.Itwouldn'thavebeenthesamepainting.ThemidwestemUnitedStateswasnotvisually视觉上interestingtomostImpressionistTheeffectofsunlightonpainters'subjectsvariessignificantlyfromplacetoHassamwasstronglyinfluencedbyhisenvironmentwhenhepaintedTheBreakfastHassamreliedonfeedbackfromotherNewYorkCityartiststoimprovehisPolarPolarbearsinhabittheArctic,ontheouterperimeters周长;边缘;oftheseaicetobeexact.Whenpolarbeardie,theirbonesalmostalwaysendupdeepdownontheflooroftheicyArcticOcean.Theybasicallydisappearforever.Recently,however,apolarbear'sjawbonewasfoundwithintheArcticCircle,onanislandinNorwaySvalbardarchipelago.Thisboneheldinavaluableinformationregardingthepolarbear'srevolutionarypastForinstance,exactlyhowlongthepolarbearhasexistedasaspecieshasbeenamatterofwilddebate.Soresearcherstooktheopportunitytoperformdatingysesonthebone,andalsotoyzeitsDNA.Thebonewasdeterminedtobeabout120,000yearsold,andtheDNAysisestablishedthatitwasindeedtheboneofapolarbear.Now,inordertomapoutthepolarbear'sgeneticprofile,researchersperformedmitochondrialDNAysis.UsuallywhenwethinkofDNA,wethinkoftheDNAthat'sincell'snucleus,butinfact,acellmitochondriaalsocontainDNA.Inthisparticularsituation,mitochondrialDNAysismademoresensethannuclearDNAysis.YourememberfromapreviouslecturethatamitochondrionistheenergyproducingstructureincellsrightWell,it(=mitochondrion题目DNA！！！hasamuorestablestructurethananucleusThat'sadistinctadvantagewhenyou'reinvestigatingancientdelicatesamples.Additionally,there'reupto1,000mitochondriamitochondriawithinasinglecell.ButthereareonlytwocopiesofnuclearDNAwithinacell.abundanceofsamplesmakesmitochondrial ysisamucheasierprocedure. 对比Asfarasgeneticsandancestryareconcernedwe'velongbeenawarethatpolarbearsareyoungspecies,evolutionarilyspeaking,andthattheybranchedofffrombrownbears.（3）Butthisjawbonefossilhashelpedusbetterestimate估计whenthatsplittingoffprobablyoccurred.Bytheway,aspartoftheirinvestigation,researchers,studiedauniquegeographicallyisolatedgroupofmodernbrownbearslivinginsoutheasternAlaska.Itturnsoutthesebrownbearshavegenesthatresembledpolarbeargenesmorethantheyresembledtesofotherbrownbears.Anyway,thejawbonefossilappearstohavecomefromapolarbearthathadlivedshortlyWell,historicallyspeakingthatis,shortlyafterpolarbearsagreedtosplitinfoadifferentspecies.Andwhatdoesallthismean?Well,becausethefossilissoold,polarbearsmusthavesurvivedEarth'slastinterglacialwarmingperiod,about45,000yearsago.ButpolarbearsareArcticanimalsandliveontheice.Inthatuniqueenvironment,howexactlydidtheymanage?Well,onetheorysuggeststhatpolarbearsmayhavebeenabletofindafewremotecoldicyplaces,suchas,well,thisSvalbardislandstoliveonuntiltheclimateeventuallycooledagain.（4）Controversially,becausethelastwarmingperiodwasactuallywarmerthantheonenow,theonemorepresentlyexperiencing.Somepeoplebelievethatpolarbearswillbeabletopullthroughagain.Butthere'ssomethingtheyarenottakingintoaccount,namely,thepaceatwhichclimatechangeisoccurringtoday.Theclimatetodayis ingwarmerataveryacceleratedrate.Polarbearsarehighlyspecializedspecies.Itisunrealistictoexpectthemtobeabletoadaptinsuchashortwindowoftime,incidentally,theclimateisn'ttheonlyfactorthatmighthaveaneffectonthepolarbear'sfuture.（5）ThishybridwasaresultofapolarbearandagrizzlybearmatingYouseeitseemsthatgrizzlybearsinCanadahavebeenmovingnorthwardintrudingonthepolarbear'sterritory.Thisisactuallythetimethatwe'veseensuchahybridinthewildbutit'spossiblethathybridizationcouldoccurmoreandmorefrequently,resultinginincreasingnumbersofoffspringthatcannolongerbeconsideredtruepolarbears.Andifthatpatterncontinuedovertime,well...WhatisthemainpurposeoftheTocomparethebehaviorsofthreedifferentbearToexaminechangestothehabitatinwhichpolarbearsTodiscussrecentinsightsintopolarbearToillustrateanewmethodofDNAysisusedinclimateWhydidtheresearchersthattheprofessormentionsusemitochondrialDNAfortestinginsteadofnuclearDNA?MitochondrialDNAhasamorestablestructurethannuclearDNAMitochondrialDNAhasashthatismoreeasilyidentifiablethanthatofnuclearMitochondrialDNAispresentinlargertiesincellsthannuclearMitochondrialDNAysisisabetter-understoodresearchtoolthannuclearDNAWhatpointdoestheprofessormakeaboutbrownTheynowcomparewithpolarbearsforfood-andTheyaretheancestorsofpolarTheyfacethesameenvironmentalthreataspolarTheirjawbonescanbeeasilydistinguishedfromthoseofpolarAccordingtotheprofessor,whatdoresearchersbelieveabouttheSvalbardPolarbearscameintoexistenceasaspeciesontheTheseparateislandswereoncejoinedtogetherinasinglelargeInterbreedingbetweenpolarbearsandaspeciesofbrownbearoccurredontheTheislandsprovidedarefugeforpolarbearsduringanancientwarmingWhatdoestheprofessorimplywhenshediscussesthecurrentwarmingThecurrentwarmingperiodisprogressingmoreslowlythanpreviouswarmingArctictemperaturestodayaresimilartotemperaturesduringpreviouswarmingThefastpaceofthecurrentwarmingperiodwillthreatenpolarbears'long-Listenagaintopartofthelecture.Thenanswerthequestion.“YouseeitseemsthatgrizzlybearsinCanadahavebeenmovingnorthward,intrudingonthepolarbear'sterritory.Thisisactuallythetimethatwe'veseensuchahybridinthewild,butit'spossiblethathybridizationcouldoccurmoreandmorefrequently,resultinginincreasingnumbersofoffspringthatcannolongerbeconsideredtruepolarbears.Andifthatpatterncontinuedovertime,well...”Whydoestheprofessorimplywhenshesaysthis:butit'spossiblethathybridizationcouldoccurmoreandmorefrequently,resultinginincreasingnumbersofoffspringthatcannolongerbeconsideredtruepolarbears.Andifthatpatterncontinuedovertime,well..ThesizeofthegrizzlybearpopulationwillsoonThefutureofthepolarbearasadistinctspeciesmightbeatHybridizationhasalreadydiminishedthepolarbearpopulationwithinashortperiodofHybridspeciesdonotadaptwelltosuddenchangesintheCCBDDNepenthese-小作业Sowe'vebeenlookingatvarietiesofcarnivorousplantspecies,plantsthatcaptureandconsumeinsects.AndtodayI'dliketointroduceanother.Onethat'softenreferredtoasthepitcher猪笼草，捕虫草plant.ThescientificnameforthepitcherplantisnepenthesAhundredorsospeciesofnepenthesfoundintheforestsofSoutheastAsiahaveavarietyofshsandsizes.Butsincethesoiltheregenerallylacksadequatenutrientstheseplantsneedtosupplementthenutritionalintakeoftheroots.Andhowdotheydothis?Well,theyhavepitchers,modifiedleaves(thatarefilledwithfluid(thtastrapsforinsects)(whichfallintothisfluidandaredigestedtheretosupplyadditionalnutritionfortheplant)).（2）Now, itappearsthatthenepenthes'methodofcatchingpray,mostlyantsisprettybasic,that pitfall陷阱 ingpitcherpart pitfall陷阱 ing怀疑的antmightjustslip跌倒，滑downinto.Andthishasbeenalongheldviewofbotanists植物学家.ButinvestigationintheforestofBorneohasrevealedthatsomenepenthesarefarmoreactiveincatchingtheirpreythanpreviouslythought.Okay.ofall,there'sarim边，缘，框aroundthetopofthepitcher.Thisiscalledtheperistome.Andalongtheinsideoftheperistomeareglandsthatsecreteasweetnectarthat.Well,it'sthesmellofthisnectarthatluresthepreyintothepitcher（4-1）.Andinsidethepitcherjustbelowtheperistome,botanistsnoticetoawaxylayer,onethat’ssmoothandslippery（3）Anditsinsectsdiveinsidetogetthenectar.Thiswaxylayerpreventsthemfrommaintainingafoothold立足处sotheyfallinfotheliquidbelowandareunabletoclimbbackupandesc.Foralongtimethiswaxyzonewasthoughttobeessentialfortheplanttotrapitsprey.Butrecently,observationoftheseplantsinthelabrevealedthatinsectsoftenfallintothepitcherwithoutevertouchingthewaxylayer.Andevenmoresurprisingwasthediscoverythatsomespeciesofnepenthesdon'tevenhavethislayer.That'sright.Somespecieshavethislayer,butothersdon’t.Andthespecieswithoutthewaxylayerarejustaseffectiveincatchingprey.Well,botanistswerecuriousaboutthisofcourse.SosomeofthemwentintotheforestsofBorneototplantslikethese,oneswithoutawaxylayer.Andtheyobservedagainandagainthatmostsinceplantsurfacesusually theantsthatclimbedontonepenthes'peristomesimplywanderedoffagain,unharmed安然无恙，未受伤的.Butonedaytheresearchersreturnedtothestudysiteafterarainstormandweresurprisedtoseethateveryantthatsteppedintooneoftheseperistomesslippedrightdownintothepitcher.Andwhentheylookedintothepitchertheynoticedlotsofantsalreadysinceplantsurfacesusually r.Butitturnsoutthatwhentheperistomeofoneofthesenepenthesplantsiswet,itholdswater.Soitssurfacegetsextremelyslipperyandinsectsliderightoffanddropdownintothetrap.（4-2）Andtheresearchersdiscoveredsomethingelsetoothattheperistomeswerewetfromearlyeveninguntilearlymorningwhetheritwasrainingornot不管是不是下雨Andthisdidn'tseemtobesimplytheresultofwater(condensing凝结，浓缩fromtheairwhenitgetscooler).ResearchersalsonoticedanincreaseintheamountofnectarproducedintheeveningAndtestsshowedthatnectarabsorbsmoisturefromtheairandthishelpskeeptherimwet.Oneresearchersuggestedyetanotherpossibility.Aplantmayevenregulate调整，控制thedegreeofwetnessbychangingtheamountofnectaritsecretsHardtobelieve?Oh,there'smore,mostbotanistshadassumedthatcarnivorousplantswerealwaysreadytocatchprey,butherewehaveaplantwiththetrapmechanism（生）机制，结构，手法技巧thatisdependent依赖的oratleastinpartontheweatheranditsometimesworksandsometimesdoesn't.Howcouldthatbeeffective?Well,someoftheseresearchershypothesizethat（5）it'sforthesamereasonssomeanimalshuntonlyintermittently间歇地，断断续续地tomakeitmoredifficultforpreytopredicttheirattacks,becausethenpreycoulddevelopcountermeasurestoavoidthem.Forexample,antsoftensendlonescouts侦察tosearchforfood.Ifascoutfindsomeandreturnsunharmed,italerts提醒，警戒otherantswhichthenstreamouttofindasourceofthefood.It’spossiblethatwhentheseantsreachthenepenthesplant,itsperistomewillbewet.Soinsteadoffindingfood,they'llbethenepenthes'maincourse.WhatisthislecturemainlyAtypicalNepentheshabitatinNortheastAsiahabitatNewresearchfindingsregardingthelifecycleofNepenthesplantsAcomparisonofthepredatorystrategiesofcarnivorousplantsandAnunusualcharacteristicofsomespeciesofNepenthesWhydoestheprofessormentionthesoilintheforestsofSoutheasternTosuggestthatNepenthesplantsarenotnativetothatregionToexplainwhyNepenthesplantsneedtotrapToillustrateadifferencebetweenNepenthesandothercarnivorousplantsToprovideanexplanationforthedifferent sandsizesofNepenthesAccordingtotheprofessorwhatpurposeisservedbythewaxylayeroftheNepenthesItattractsinsectstoentertheplant.Itproducestheplant’sdigestiveenzymes.ItcausesinsectstoslidedowninfothefluidintheItsecretesastickysubstancethatkeepstrappedinsectsfromesca.无AccordingtotheprofessorwhatfeaturesoftheNepenthesPeristomehelptheplantcatchClickontwoIthasglandsthatproduceItssurfacedoesnotrepelIthascolorfulmarkingsthatconfusesomeinsects.TheprofessorexplainsthattheNepenthesplantstrapmechanismisnotconsistentlyactivatedbythepresenceoftheant.Whatdoestheprofessorimplyaboutthisinconsistency?定位最后一层ItmightenabletheplanttocapturemorepreyoverthelongItmightexplainwhytheplanthasotherwaysofcapturingprey.Itmightresultfromtheplantsneedforrestingperiods.Itmightresultfromtheseverityoftropicalrains.Whatdoestheprofessorimplywhenshesaysthis?3分48秒-4分Shehasfottentoincludesomeimportantdetails.无Materialshehasjustpresentedwillbeexplainedbyherfollowingstatements.根本Studentsmaybesurp