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1、词义猜测阅读理解专题四:词义猜测题LifeintheClearTransparentanimalsletlightpassthroughtheirbodiesthesamewaylightpassesthroughawindow.Theseanimalstypicallylivebetweenthesurfaceoftheoceanandadepthofabout3,300feet—asfarasmostlightcanreach.Mostofthemareextremelydelicateandcanbedamagedbyasimpletouch.So
2、nkeJohnsen,ascientistinbiology,says,“Theseanimalslivethroughtheirlifealone.Theynevertouchanythingunlessthey'reeatingit,orunlesssomethingiseatingthem.”Andtheyareasclearasglass.Howdoesananimalbecomeseethrough?It'strickierthanyoumightthink.Theobjectsaroundyouarevisiblebecausetheyint
3、eractwithlight.Lighttypicallytravelsinastraightline.Butsomematerialsslowandscatter(散射)light,bouncingitawayfromitsoriginalpath.Othersabsorblight,stoppingitdeadinitstracks.Bothscatteringandabsorptionmakeanobjectlookdifferentfromotherobjectsaroundit,soyoucanseeiteasily.Butatranspare
4、ntobjectdoesn'tabsorborscatterlight,atleastnotverymuch.Lightcanpassthroughitwithoutbendingorstopping.Thatmeansatransparentobjectdoesn'tlookverydifferentfromthesurroundingairorwater.Youdon'tseeit—youseethethingsbehindit.Tobecometransparent,ananimalneedstokeepitsbodyfromabsorbingor
5、scatteringlight.Livingmaterialscanstoplightbecausetheycontainpigments(色素)thatabsorbspecificcolorsoflight.Butatransparentanimaldoesn'thavepigments,soitstissueswon'tabsorblight.AccordingtoJohnsen,avoidingabsorptionisactuallyeasy.Therealchallengeispreventinglightfromscattering.Anima
6、lsarebuiltofmanydifferentmaterials—skin,fat,andmore—andlightmovesthrougheachatadifferentspeed.Everytimelightmovesintoamaterialwithanewspeed,itbendsandscatters.Transparentanimalsusedifferenttrickstofightscattering.Someanimalsaresimplyverysmallorextremelyflat.Withoutmuchtissuetosca
7、tterlight,itiseasiertobeseethrough.Othersbuildalarge,clearmassofnonlivingjellylike(果冻状的)materialandspreadthemselvesoverit.Largertransparentanimalshavethebiggestchallenge,becausetheyhavetomakeallthedifferenttissuesintheirbodiesslowdownlightexactlyasmuchaswaterdoes.Theyneedtolookun
8、iform.Buthowthey'redoingitisstillunknown