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时间:2019-11-27
《中考英语复习:难度较大的阅读文章含答案五.doc》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、第一篇“Salty”RicePlantBoostsHarvestsBritishscientistsarebreedinganewgenerationofriceplantsthatwillbeabletogrowinsoilcontainingsaltwater.Theirworkmayenableabandonedfarmstobecomeproductiveoncemore.TimFlowersandTonyYeo,fromSussexUniversity’sSchoolofBiologicalSciences,havespentseveralyears
2、researchinghowcrops,suchasrice,couldbemadetogrowinwaterthathasbecomesalty.Thepairhaverecentlybegunathree-yearprogramme,fundedbytheBiotechnologyandBiologicalSciencesResearchCouncil,toestablishwhichgenesenablesomeplantstosurvivesaltyconditions.Theaimistobreedthiscapabilityintocrops,st
3、artingwithrice.Itisestimatedthateachyearmorethan10mhectares(公顷)ofagriculturallandarelostbecausesaltgetsintothesoilandstunts(妨碍生长)plants.Theproblemiscausedbyseveralfactors.Inthetropics,mangroves(红树林)thatcreateswamps(沼泽)andtraditionallyformedbarrierstoseawaterhavebeencutdown.IntheMedi
4、terranean,aseriesofdroughtshavecausedthewatertabletodrop,allowingseawatertoseep(渗透)in.inLatinAmerica,irrigationoftencausesproblemswhenwaterisevaporated(蒸发)bytheheat,leavingsaltdepositsbehind.Excesssaltthenenterstheplantsandpreventsthemfunctioningnormally.Heavyconcentrationsofmineral
5、sintheplantsstopthemdrawingupthewatertheyneedtosurvive.Toovercometheseproblems,FlowersandYeodecidedtobreedriceplantsthattakeinverylittleslatandstorewhattheydoabsorbincellsthatdonotaffecttheplants‘growth.Theyhavestartedtobreedthesecharacteristicsintoanewricecrop,butitwilltakeabouteig
6、htharvestsbeforetheresultingseedsarereadytobeconsideredforcommercialuse.Oncethecharacteristicsforsurvivingsaltysoilareknown,FlowersandYeowilltrytobreedtheappropriategenesintoallmannersofcropsandplants.Landthathasbeenabandonedtonaturewillthenbeabletobloomagain,providingmuchneededfood
7、inthepoorercountriesoftheworld.31WhichofthefollowingstatementsaboutFlowersandYeoistrue?ATheyarestudentsatSussexUniversity.BTheyarericebreeders.CTheyarehusbandandwife.DTheyarecolleaguesataninstitutionofhigherlearning.32FlowersandYeohavestartedaprogrammeAtofindwaystopreventwaterpollut
8、ion.Btoidentifygene
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