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1、【王鑫托福阅读】托福TPO13-2阅读文本TPO13TP013-2BiologicalClocks1•Theword"Consequently”inthepassageisclosestinmeaningtoAThereforeBAdditionallyCNeverthelessDMoreover2.Inparagraph1,theexperimentonthefungusNeurosporaismentionedto订lustrateAtheexistenceofweeklyperiodsofactivityaswellasdailyonesBthefindingofevidencetha
2、torganismshaveinternalclocksCtheeffectofspaceontheinternalclocksoforganismsDtheisolationofonepartofanorganism，scyclestudy3・Accordingtoparagraph1,al1thefollowingaregenerallyassumedtobetrueEXCEPT:AItisimportantforanimals'dailyactivitiestobecoordinatedwithrecurringeventsintheirenvironment.BEukaryotesh
3、aveinternalclocks.CTherelationshipbetweenbiologicalfunctionandenvironmentalcyclesisatopicofintenseresearch.DAnimals'dailyrhythmsaremoredepcndentonexternalcuesthanoninternalclocks-Survivalandsuccessfulreproductionusuallyrequiretheactivitiesofanimalstobecoordinatedwithpredictableeventsaroundthem・Cons
4、equently,thetimingandrhythmsofbiologicalfunctionsmustcloselymatchperiodiceventslikethesolarday,thetides,thelunarcycle,andtheseasons・Therelationsbetweenanimalactivityandtheseperiods,particularlyforthedailyrhythms,havebeenofsuchinterestandimportancethatahugeamountofworkhasbeendoneonthemandthespecialr
5、esearchfieldofchronobiologyhasemerged・Normally,theconstantlychanginglevelsofananimaTsactivity—sleeping,feeding,moving,reproducing,metabolizing,andproducingenzymesandhormones,Jforexample一arewellcoordinatedwithrmw・,▲,environmentalrhythms,butthekeyquestioniswhethertheanimal，sscheduleisdrivenbyexternal
6、cues,suchassunriseorsunset,orisinsteaddependentsomehowoninternaltimersthatthemselvesgeneratetheobservedbiologicalrhythms・Almostuniversally,biologistsaccepttheideathatalleukaryotes(acategorythatincludesmostorganismsexceptbacteriaandcertainalgae)haveinternalclocks.Byisolatingorganismscompletelyfromex
7、ternalperiodiccues,biologistslearnedthatorganismshaveinternalclocks-Forinstance,apparentlynormaldailyperiodsofbiologicalactivityweremaintainedforaboutaweekbythefungusNeurosporawhenitwasintentionallyisolated
