2015年职称英语理工a阅读理解必考文章 字典版

《2015年职称英语理工a阅读理解必考文章 字典版》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、44FJgong-a第九篇AnEssentialScientificProcess一个至关重要的科学过程Alllifeontheearthdependsupongreenplants.Usingsunlight,theplantsproducetheirownfood.Thenanimalsfeedupontheplants.Theytakeinthenutrientstheplantshavemadeandstored.Butthat’snotall.Sunlightalsohelpsaplantproduceoxygen.Som

2、eoftheoxygenisusedbytheplant,butaplantusuallyproducesmoreoxygenthanituses.Theexcessoxygenisnecessaryforanimalsandotherorganismstolive.Theprocessofchanginglightintofoodandoxygeniscalledphotosynthesis.Besideslightenergyfromthesun,plantsalsousewaterandcarbondioxide.Thewat

3、ergetstotheplantthroughitsroots.Thecarbondioxideenterstheleavesthroughtinyopeningscalledstomata.Thecarbondioxidetravelstochloroplasts,specialcellsinthebodiesofgreenplants.Thisiswherephotosynthesistakesplace.Chloroplastscontainthechlorophyllsthatgiveplantstheirgreencolo

4、r.Thechlorophyllsarethemoleculesthattraplightenergy.Thetrappedlightenergychangeswaterandcarbondioxidetoproduceoxygenandasimplesugarcalledglucose.Carbondioxideandoxygenmoveintoandoutofthestomata.Watervaporalsomovesoutofthestomata.Morethan90percentofwateraplanttakesinthr

5、oughitsrootsescapesthroughthestomata.Duringthedaytime,thestomataofmostplantsareopen.Thisallowscarbondioxidetoentertheleavesforphotosynthesis.Asnightfalls,carbondioxideisnotneeded.Thestomataofmostplantsclose.Waterlossstops.Ifphotosynthesisceased,therewouldbelittlefoodor

6、otherorganicmatterontheearth.Mostorganismswoulddisappear.Theearth’satmospherewouldnolongercontainoxygen.Photosynthesisisessentialforlifeonourplanet.练习：1．Inthefirstparagraph，theword“excess”means.B　extra.2．Whichofthefollowingdoesnotmovethroughaplant’sstomata?D　Food.3．Int

7、hetitle,thetermEssentialScientificProcessreferstoA　photosynthesis.4．ThispassageisprimarilydevelopedbyA　explainingaprocess.5．AnothergoodtitleforthispassagewouldbeC　HowPhotosynthesisWorks.第二十二篇RealWorldRobots现实世界中的机器人Whenyouthinkofarobot,doyouenvisionashiny,metallicdevic

8、ehavingthesamegeneralshapeasahumanbeing,performinghumanlikefunctions,andrespondingtoyourquestionsinamonotonevoiceacce