其他-這次托福

有了第一次考托的經(jīng)驗，我備考的時候就主攻寫作和。像什么"Currently,theissueofwhetherornot..."，直接就拿來用了。第二次的時候就學聰明了，獨立寫作方面，仔細學習了OG的3/4/5和別人的范4b、別人的文章，比如王子睿的范可以拿來看看，看看他是怎么開頭的，以及文章段落內(nèi)和段落間的銜看網(wǎng)上的經(jīng)驗，覺得自己之前有兩個不足：一是原文太多；而是的內(nèi)容有遺漏。原文多那就只能從拓展詞匯量入手了，這個我也沒太注意，就是盡量別老是重復使用同個詞吧。內(nèi)容的話可以和部分一起練，后面有講 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-Ce?zanne85=105=4-IceMaking86=5-River87=33-FlotsamListentopartofalectureinanEarthscienceOK.Beforewefinishclass,I'dliketobrieflytalkaboutsomethingelse.Hasanyoneeverheardofsomethingcalledflotsam廢料;浮貨;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這也許是正統(tǒng)的，也許是非傳統(tǒng)的科學學科.Infact,thankstoflotsamscienceandthesetravellingbathtoysandotherharmlessstuffthatdroppedoffshipslikeathleticshoes,sportsequipment,younameit.Scientistsnowknowalotmorethantheyusedto,aboutthecurrentsinthenorthernPacific.Thatinformation,inturn,hasallowedscientiststoidentifylongtermchangesinwatertemperatureandsalinitytheamountofsaltinthewaterinthesecurrents.（3結(jié)果）Beforeflotsamscience,scientistshavebeentryingtodeterminetheseinformationforyearsbyusingexpensivescientificdevicesthattheywouldsetadriftintheocean.Butthereareproblemswiththesedevices.Foronethingtheyneedtotravelagreatdepthasmuchastwokilometersdownbecauseiftheyrideonthesurfaceoftheocean,theirsensescouldbeobstructedbyalgae,otheranismthatthriveinthesun-litportion 照亮的部分oftheocean.（4問題的具體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優(yōu)點)andofferarewardinthreedifferentlanguagesontheduck,hedropped90ofthemdownthemoulinhewasresearching.Nowhehasn'tactuallyhadanyoftheseducksreturnedyet,butheremainshopefulthatsomeonewillfindtheduckandreturntohim.WhatisthelecturemainlyUnusualfeaturesofmeltingEffectsofoceancurrentsonglacierAnunconventionalresearAnenvironmentalproblemcausedbylargeWhydoestheprofessormentionanincidentinvolvingacargoshipinthePacificTopointoutthemainweaknessofflotsamToexplaintheoriginsofflotsamToemphasizetheongoingneedforflotsamToprovideanexampleofhowflotsamsciencebenefitsAccordingtotheprofessor，whatwerescientistsabletoidentifyinPacificOceancurrentsasaresultofflotsamscienceLong-termchangesintemperatureandsaltFluctuationsinthegrowthofTherelationshipbetweenoceandepthandwaterHowwindsaffectwaterspeedandWhydoestheprofessormentionanismsthatthriveintheupperportionsoftheTocontrastglacialmeltwaterwithoceanTodiscussalimitationofacertaintypeofscientificToindicateanewresearchareatowhichflotsamsciencecanToprovideanexampleofhowoceancurrentsaffectwaterWhyhasonescientistusedtoyduckstostudymoulinsClickon2TheycanwithstandcoldtemperaturesandhighTheydonotharmtheTheycanbeeasilyequippedwithelectronicmeasuringTheyareveryWhydoestheprofessorsaythis:OnescientistsetouttodeterminewheremeltwaterfromaglacierinGreenlandendsup.Itwasintheneighboringbodyofwater！一位科學家著手確定格Toindicatetheresearcher'sthoughtToexpresssurpriseat eofanToadmittonotknowinghowtoanswertheresearcher'sToquestionaflawedassumptionmadebytheresearcherCBABADBInourstudiesofimpressionism,we'vealreadyseenhowtheoutdoors..em…h(huán)owoutdoorsettingsandnaturalsubjectsfigureprominently突出體現(xiàn)inEuropeanimpressionist印象派畫paintingsofthe19thcentury.Natureandnaturallandscswerekeytotheartist'snewresourceoflightandcolorwhichplacesanemphasisontheartist'simpressionswhattheartistactuallysawindifferentlightconditionsratherthanonidealizedofplacesandscenes.強調(diào)藝術(shù)家的印象，藝術(shù)家在不同的光照條件下所看到ButthesearetheonlysubjectsweseeinthepaintingsofChildHasomeHasomewasoneofthemostimportantimpressionistpaintersintheUnitedStates.Hewasuniquefor…em…h(huán)isbodyofworkrepresentsareallyinterestingdichotomyofbothruralandurbanelements.Nowdon'tgetmewrong,likethebestmajorityofimpressionistsHasomedidpaintmanyruraloutdoorthings.ButthecityespeciallyNewYorkcitywereintomanyofhisworktoo.Yousee,imagineimpressionismdevelopedduringtheindustrialage,averydynamictimeinUShistory,thelate1800s,early1900s.Everythingwaschanging,howpeoplelive,wheretheylive,theirjob.Increasingnumbersofpeoplefromthroughouttheworldimmigratedheretofillthenewfactoryjobandnaturallytheyflockedtothebigcitieswherethosejobswere.Sothecitiesgrewverynoisyandcrowded.Mostoftheearlyimpressionistsreactedto（2-藝術(shù)家的反映）thisbyusinganarttocounterthebusyurbanenvironment.Incontrast,allthesechangeandcommersion,theirpaintingsemphasisnature,peace,andpermanent.ManyoftheseartistsmaintainstudiosinNewYorkcityorBoston,buttheyweresummoned召喚;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特點）Bystructuringthesceneinthisway,HasomelinksthewomanandherimmediateenvironmenttothecityscbehindherEmm…thesamethingwithcolor（4-2停頓，特點）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那幅畫）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視覺上interestingtomostImpressionistTheeffectofsunlightonpainters'subjectsvariessignificantlyfromplacetoHassamwasstronglyinfluencedbyhisenvironmentwhenhepaintedTheBreakfastHassamreliedonfeedbackfromotherNewYorkCityartiststoimprovehisPolarPolarbearsinhabittheArctic,ontheouterperimeters周長;邊緣;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題目DNA?。?！hasamuorestablestructurethananucleusThat'sadistinctadvantagewhenyou'reinvestigatingancientdelicatesamples.Additionally,there'reupto1,000mitochondriamitochondriawithinasinglecell.ButthereareonlytwocopiesofnuclearDNAwithinacell.abundanceofsamplesmakesmitochondrial ysisamucheasierprocedure. 對比Asfarasgeneticsandancestryareconcernedwe'velongbeenawarethatpolarbearsareyoungspecies,evolutionarilyspeaking,andthattheybranchedofffrombrownbears.（3）Butthisjawbonefossilhashelpedusbetterestimate估計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-小作業(yè)Sowe'vebeenlookingatvarietiesofcarnivorousplantspecies,plantsthatcaptureandconsumeinsects.AndtodayI'dliketointroduceanother.Onethat'softenreferredtoasthepitcher豬籠草，捕蟲草plant.ThescientificnameforthepitcherplantisnepenthesAhundredorsospeciesofnepenthesfoundintheforestsofSoutheastAsiahaveavarietyofshsandsizes.Butsincethesoiltheregenerallylacksadequatenutrientstheseplantsneedtosupplementthenutritionalintakeoftheroots.Andhowdotheydothis?Well,theyhavepitchers,modifiedleaves(thatarefilledwithfluid(thtastrapsforinsects)(whichfallintothisfluidandaredigestedtheretosupplyadditionalnutritionfortheplant)).（2）Now, itappearsthatthenepenthes'methodofcatchingpray,mostlyantsisprettybasic,that pitfall陷阱 ingpitcherpart pitfall陷阱 ing懷疑的antmightjustslip跌倒，滑downinto.Andthishasbeenalongheldviewofbotanists植物學家.ButinvestigationintheforestofBorneohasrevealedthatsomenepenthesarefarmoreactiveincatchingtheirpreythanpreviouslythought.Okay.ofall,there'sarim邊，緣，框aroundthetopofthepitcher.Thisiscalledtheperistome.Andalongtheinsideoftheperistomeareglandsthatsecreteasweetnectarthat.Well,it'sthesmellofthisnectarthatluresthepreyintothepitcher（4-1）.Andinsidethepitcherjustbelowtheperistome,botanistsnoticetoawaxylayer,onethat’ssmoothandslippery（3）Anditsinsectsdiveinsidetogetthenectar.Thiswaxylayerpreventsthemfrommaintainingafoothold立足處sotheyfallinfotheliquidbelowandareunabletoclimbbackupandesc.Foralongtimethiswaxyzonewasthoughttobeessentialfortheplanttotrapitsprey.Butrecently,observationoftheseplantsinthelabrevealedthatinsectsoftenfallintothepitcherwithoutevertouchingthewaxylayer.Andevenmoresurprisingwasthediscoverythatsomespeciesofnepenthesdon'tevenhavethislayer.That'sright.Somespecieshavethislayer,butothersdon’t.Andthespecieswithoutthewaxylayerarejustaseffectiveincatchingprey.Well,botanistswerecuriousaboutthisofcourse.SosomeofthemwentintotheforestsofBorneototplantslikethese,oneswithoutawaxylayer.Andtheyobservedagainandagainthatmostsinceplantsurfacesusually theantsthatclimbedontonepenthes'peristomesimplywanderedoffagain,unharmed安然無恙，未受傷的.Butonedaytheresearchersreturnedtothestudysiteafterarainstormandweresurprisedtoseethateveryantthatsteppedintooneoftheseperistomesslippedrightdownintothepitcher.Andwhentheylookedintothepitchertheynoticedlotsofantsalreadysinceplantsurfacesusually r.Butitturnsoutthatwhentheperistomeofoneofthesenepenthesplantsiswet,itholdswater.Soitssurfacegetsextremelyslipperyandinsectsliderightoffanddropdownintothetrap.（4-2）Andtheresearchersdiscoveredsomethingelsetoothattheperistomeswerewetfromearlyeveninguntilearlymorningwhetheritwasrainingornot不管是不是下雨Andthisdidn'tseemtobesimplytheresultofwater(condensing凝結(jié)，濃縮fromtheairwhenitgetscooler).ResearchersalsonoticedanincreaseintheamountofnectarproducedintheeveningAndtestsshowedthatnectarabsorbsmoisturefromtheairandthishelpskeeptherimwet.Oneresearchersuggestedyetanotherpossibility.Aplantmayevenregulate調(diào)整，控制thedegreeofwetnessbychangingtheamountofnectaritsecretsHardtobelieve?Oh,there'smore,mostbotanistshadassumedthatcarnivorousplantswerealwaysreadytocatchprey,butherewehaveaplantwiththetrapmechanism（生）機制，結(jié)構(gòu)，手法技巧thatisdependent依賴的oratleastinpartontheweatheranditsometimesworksandsometimesdoesn't.Howcouldthatbeeffective?Well,someoftheseresearchershypothesizethat（5）it'sforthesamereasonssomeanimalshuntonlyintermittently間歇地，斷斷續(xù)續(xù)地tomakeitmoredifficultforpreytopredicttheirattacks,becausethenpreycoulddevelopcountermeasurestoavoidthem.Forexample,antsoftensendlonescouts偵察tosearchforfood.Ifascoutfindsomeandreturnsunharmed,italerts提醒，警戒otherantswhichthenstreamouttofindasourceofthefood.It’spossiblethatwhentheseantsreachthenepenthesplant,itsperistomewillbewet.Soinsteadoffindingfood,they'llbethenepenthes'maincourse.WhatisthislecturemainlyAtypicalNepentheshabitatinNortheastAsiahabitatNewresearchfindingsregardingthelifecycleofNepenthesplantsAcomparisonofthepredatorystrategiesofcarnivorousplantsandAnunusualcharacteristicofsomespeciesofNepenthesWhydoestheprofessormentionthesoilintheforestsofSoutheasternTosuggestthatNepenthesplantsarenotnativetothatregionToexplainwhyNepenthesplantsneedtotrapToillustrateadifferencebetweenNepenthesandothercarnivorousplantsToprovideanexplanationforthedifferent sandsizesofNepenthesAccordingtotheprofessorwhatpurposeisservedbythewaxylayeroftheNepenthesItattractsinsectstoentertheplant.Itproducestheplant’sdigestiveenzymes.ItcausesinsectstoslidedowninfothefluidintheItsecretesastickysubstancethatkeepstrappedinsectsfromesca.無AccordingtotheprofessorwhatfeaturesoftheNepenthesPeristomehelptheplantcatchClickontwoIthasglandsthatproduceItssurfacedoesnotrepelIthascolorfulmarkingsthatconfusesomeinsects.TheprofessorexplainsthattheNepenthesplantstrapmechanismisnotconsistentlyactivatedbythepresenceoftheant.Whatdoestheprofessorimplyaboutthisinconsistency?定位最后一層ItmightenabletheplanttocapturemorepreyoverthelongItmightexplainwhytheplanthasotherwaysofcapturingprey.Itmightresultfromtheplantsneedforrestingperiods.Itmightresultfromtheseverityoftropicalrains.Whatdoestheprofessorimplywhenshesaysthis?3分48秒-4分Shehasfottentoincludesomeimportantdetails.無Materialshehasjustpresentedwillbeexplainedbyherfollowingstatements.根本Studentsmaybesurp