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课时作业(十七)
Ⅰ.阅读理解
[2017·安徽淮南二模]
DoPeru'spotatoeshavetherightstuff?That'sthequestionscientistswillbeaskinginLimanextmonth,whenaselectionofpotatoeswillbeginundergoingteststodeterminewhethertheyarefittogrowonMars.
NASA,theUSspaceagency,isconductingthepioneeringexperimenttogetherwithLima'sInternationalPotatoCenter.
TheywillcultivateahundredselectedvarietiesinMarslikeconditionsthatcouldeventuallypavethewayforbuildingadomeontheRedPlanetforfarmingthevegetable.Oftheselectedcandidates,40arenativetotheAndesMountains,conditionedtogrowindifferentecologicalzones,canstandsuddenclimatechangesandreproduceinrockyareas.Theother60areimprovedvarieties,abletosurvivewithlittlewaterandsalt.Theyarealsoimmunetoviruses.Thosethatpassthetestsmustmeetafinalcriterion—theymustbeablenotonlytogrowwellonMarsbutalsoreproduceinlargequantities.“We'realmost100percentcertainthatmanyoftheselectedpotatoeswillpassthetests,”saidJulioValdiviaSilva,a PeruvianNASAastrobiologist(太空生物学家)whoistakingpartintheambitiousproject.Thescientistsplantotransport100kilosofsoiltoalabinLimathatwillsimulatethecomplexMartian
atmosphere—whichcontainsmostlycarbondioxide—andexposeitto
extremeultraviolet(紫外线的)radiation.Ifthevarietiesselectedfornextmonth'sexperimentdon'tadapttothedesertsoil,theresearcherswillintroducenutrients,whichwillbeprovidedbyradiation.
Infutureyears,NASAplanstobuildaMarsresearchcenterinthePeruviandesert.ItwouldcreateaperfectcopyoftheMartianlandscapeandatmosphereforfutureresearchintospacefarmingthatcouldservemannedmissionstoMarsandotherplanetsinthesolarsystem.
1.Whatisthebesttitleofthepassage?A.TransportpotatoestoPeru.
B.DeterminethevarietiesofpotatoesinPeru.C.NASAistobuildaMarsreseachcenterinPeru.
D.NASAistosimulategrowing
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