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ID:29819240
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页数:9页
时间:2018-12-24
《2019高考英语一轮复习 unit 1 tales of the unexplained 牛津译林版必修2》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、Unit1Talesoftheunexplained一、阅读理解Nowadaysmoreandmorepeoplearetalkingaboutgeneticallymodifiedfoods(GMfoods).GMfoodsdevelopfromgeneticallymodifiedorganisms(有机体),whichhavehadspecificchangesintroducedintotheirDNAbygeneticengineeringtechniques.Thesetechniquesaremuchmoreprecisewhe
2、reanorganismisexposedtochemicalstocreateanonspecificbutstablechange.Formanypeople,thehightechproductionraisesallkindsofenvironmental,ethical,healthandsafetyproblems.Particularlyincountrieswithlongfarmingtraditions,theideaseemsagainstnature.Infact,GMfoodsarealreadyverymuch
3、apartofourlives.Theywerefirstputonthemarketin1996.AthirdofthecornandmorethanhalfthecottongrownintheU.S.lastyearwastheproductofbiotechnology,accordingtotheDepartmentofAgriculture.Morethan65millionacresofgeneticallymodifiedcropswillbeplantedintheUSthisyear. Thegeneticgenieiso
4、utofthebottle.However,likeanynewproductenteringthefoodchain,GMfoodsmustbesubjectedtocarefultesting.Inwealthycountries,thedebateaboutbiotechisnotsofiercebythefactthattheyhavealargenumberoffoodstochoosefrom,andasupplythatgoesbeyondtheneeds.Indevelopingcountriesdesperatetofeed
5、fastgrowingandunderfedpopulations,thematterissimplerandmuchmoreurgent:dothebenefitsofbiotechoutweightherisks?Thestatisticsonpopulationgrowthandhungeraredisturbing.Lastyeartheworld'spopulationreached6billion.TheUNstatesthatnearly800millionpeoplearoundtheworldareunhealthy.Ab
6、out400millionwomenofchildbearingagedon'thaveenoughiron,whichmeanstheirbabiesareexposedtovariousbirthdefeats.Asmanyas100millionchildrensufferfromvitaminAdeficiency,aleadingcauseofblindness.Howcanbiotechhelp?Geneticengineeringiswidelyusedtoproduceplantsandanimalswithbetternut
7、ritionalvalues.Biotechnologistshavedevelopedgeneticallymodifiedriceandtheyareworkingonotherkindsofnutritionallyimprovedcrops.Biotechcanalsoimprovefarmingproductivityinplaceswherefoodshortagesarecausedbycropdamageattributabletodrought,poorsoilandcropviruses.1.Thepassagemainl
8、ytalksabout________.A.theworld'sfoodproblemB.thedevelopmentinbiotechC.thegenetical
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