资源描述:
《2019-2020年高考英语专题复习 词义猜测学案》由会员上传分享,免费在线阅读,更多相关内容在教育资源-天天文库。
1、2019-2020年高考英语专题复习词义猜测学案阅读理解专题四:词义猜测题LifeintheClearTransparentanimalsletlightpassthroughtheirbodiesthesamewaylightpassesthroughawindow.Theseanimalstypicallylivebetweenthesurfaceoftheoceanandadepthofabout3,300feet—asfarasmostlightcanreach.Mostofthemareextremelydelicateandcanbedamagedbya
2、simpletouch.SonkeJohnsen,ascientistinbiology,says,“Theseanimalslivethroughtheirlifealone.Theynevertouchanythingunlessthey'reeatingit,orunlesssomethingiseatingthem.”Andtheyareasclearasglass.Howdoesananimalbeeseethrough?It'strickierthanyoumightthink.Theobjectsaroundyouarevisiblebecauseth
3、eyinteractwithlight.Lighttypicallytravelsinastraightline.Butsomematerialsslowandscatter(散射)light,bouncingitawayfromitsoriginalpath.Othersabsorblight,stoppingitdeadinitstracks.Bothscatteringandabsorptionmakeanobjectlookdifferentfromotherobjectsaroundit,soyoucanseeiteasily.Butatransparen
4、tobjectdoesn'tabsorborscatterlight,atleastnotverymuch.Lightcanpassthroughitwithoutbendingorstopping.Thatmeansatransparentobjectdoesn'tlookverydifferentfromthesurroundingairorwater.Youdon'tseeit—youseethethingsbehindit.Tobeetransparent,ananimalneedstokeepitsbodyfromabsorbingorscattering
5、light.Livingmaterialscanstoplightbecausetheycontainpigments(色素)thatabsorbspecificcolorsoflight.Butatransparentanimaldoesn'thavepigments,soitstissueswon'tabsorblight.AccordingtoJohnsen,avoidingabsorptionisactuallyeasy.Therealchallengeispreventinglightfromscattering.Animalsarebuiltofmany
6、differentmaterials—skin,fat,andmore—andlightmovesthrougheachatadifferentspeed.Everytimelightmovesintoamaterialwithanewspeed,itbendsandscatters.Transparentanimalsusedifferenttrickstofightscattering.Someanimalsaresimplyverysmallorextremelyflat.Withoutmuchtissuetoscatterlight,itiseasierto
7、beseethrough.Othersbuildalarge,clearmassofnonlivingjellylike(果冻状的)materialandspreadthemselvesoverit.Largertransparentanimalshavethebiggestchallenge,becausetheyhavetomakeallthedifferenttissuesintheirbodiesslowdownlightexactlyasmuchaswaterdoes.Theyneedtolookuniform.Buthowthey'redoingit