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时间:2019-08-03
《2015职称英语理工类新增教材》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、2015职称英语理工类新增5篇旧文章新增文章理工C阅读理解第九篇:EgyptFelledbyFamine第九篇:AnEssentialScientificProcess补全短文第五篇:TheMagicofSound第五篇:ARecord-BreakingRover理工B阅读理解第二十二篇:Snowflakes第二十二篇:Real-WorldRobots补全短文第九篇:HeatIsKiller第九篇:LighteningStrikes理工A补全短文第十三篇:SleepingGiant第十三篇:AffectionateAndroids理工C阅读理解新增文章第九篇
2、 AnEssentialScientificProcessAlllifeontheearthdependsupongreenplants.Usingsunlight,theplantsproducetheirownfood.Thenanimalsfeedupontheplants.Theytakeinthenutrientstheplantshavemadeandstored.Butthat’snotall.Sunlightalsohelpsaplantproduceoxygen.Someoftheoxygenisusedbytheplant,buta
3、plantusuallyproducesmoreoxygenthanituses.Theexcessoxygenisnecessaryforanimalsandotherorganismstolive.Theprocessofchanginglightintofoodandoxygeniscalledphotosynthesis.Besideslightenergyfromthesun,plantsalsousewaterandcarbondioxide.Thewatergetstotheplantthroughitsroots.Thecarbondioxideentersth
4、eleavesthroughtinyopeningscalledstomata.Thecarbondioxidetravelstochloroplasts,specialcellsinthebodiesofgreenplants.Thisiswherephotosynthesistakesplace.Chloroplastscontainthechlorophyllsthatgiveplantstheirgreencolor.Thechlorophyllsarethemoleculesthattraplightenergy.Thetrappedlightenergychange
5、swaterandcarbondioxidetoproduceoxygenandasimplesugarcalledglucose.Carbondioxideandoxygenmoveintoandoutofthestomata.Watervaporalsomovesoutofthestomata.Morethan90percentofwateraplanttakesinthroughitsrootsescapesthroughthestomata.Duringthedaytime,thestomataofmostplantsareopen.Thisallowscarbondi
6、oxidetoentertheleavesforphotosynthesis.Asnightfalls,carbondioxideisnotneeded.Thestomataofmostplantsclose.Waterlossstops.Ifphotosynthesisceased,therewouldbelittlefoodorotherorganicmatterontheearth.Mostorganismswoulddisappear.Theearth’satmospherewouldnolongercontainoxygen.Photosynthesisisessen
7、tialforlifeonourplanet.词汇:nutrientn.营养物organismn.生物体,有机体carbondioxiden.二氧化碳chloroplastn.叶绿体moleculen.分子vaporn.水蒸气oxygenn.氧气photosynthesisn.光合作用chlorophylln.叶绿素glucosen.葡萄糖ceasev.停止注释:1.Thenanimalsfeedupontheplants.动物以植物为食。练习:1.Inthefirstparagraph,t
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