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1、环球雅思广州学校：guangzhou.gedu.org 环球雅思小班入学测试题READING:NUMBEROFQUESTIONS:40TIMEALLOWED:60minutes新-11版ReadingREADINGPASSAGE1Youshouldspendabout20minutesonQuestions1-14whicharebasedonReadingPassage1onpages9and10.SpidersilkcutsweightofbridgesAstrong,lightbio-materialmadeby
2、genesfromspiderscouldtransformconstructionandindustryAScientistshavesucceededincopyingthesilk-producinggenesoftheGoldenOrbWeaverspiderandusingthemtocreateasyntheticmaterialwhichtheybelieveisthemodelforanewgenerationofadvancedbio-materials.Thenewmaterial,biosilk,whichhasbe
3、enspunforthefirsttimebyresearchersatDuPont,hasanenormousrangeofpotentialusesinconstructionandmanufacturing.BTheattractionofthesilkspunbythespiderisacombinationofgreatstrengthandenormouselasticity,whichman-madefibreshavebeenunabletoreplicate.Onanequal-weightbasis,spidersil
4、kisfarstrongerthansteelanditisestimatedthatifasinglestrandcouldbemadeabout10mindiameter,itwouldbestrongenoughtostopajumbojetinflight.Athirdimportantfactoristhatitisextremelylight.Armyscientistsarealreadylookingatthepossibilitiesofusingitforlightweight,bullet-proofvestsand
5、parachutes.CForsometime,biochemistshavebeentryingtosynthesizethedrag-linesilkoftheGoldenOrbWeaver.Thedrag-linesilk,whichformstheradialarmsoftheweb,isstrongerthantheotherpartsofthewebandsomebiochemistsbelieveasyntheticversioncouldprovetobeasimportantamaterialasnylon,whichh
6、asbeenaroundfor50years,sincethediscoveriesofWallaceCarothersandhisteamusheredintheageofpolymers.DTorecreatethematerial,scientists,includingRandolphLewisattheUniversityofWyoming,firstexaminedthesilk-producingglandofthespider.“Wetookouttheglandsthatproducethesilkandlookedat
7、thecodingfortheproteinmaterialtheymake,whichisspunintoaweb.WethenwentlookingforcloneswiththerightDNA,”hesays.9环球雅思广州学校：guangzhou.gedu.org EAtDuPont,researchershaveusedbothyeastandbacteriaashoststogrowtherawmaterial,whichtheyhavespunintofibres.RobertDorsch,Dupont
8、’sdirectorofbiochemicaldevelopment,saystheglobulesofprotein,comparablewithmarblesinanegg,areharv
