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课时作业(十七)选修Unit2Whatishappinesstoyou?.阅读理解A2021开封市高三第一次模拟Dontlikeseedsinyourtomatoes? Youmightbepleasedtoknowthatseedlessoneshavebeencreatedbygeneediting.Thiscouldcreateawiderangeofseedlessfruits, butfewmayeverbeseeninthesupermarketifregulatorsdecidetotreatgeneeditedcropsinthesamewayasgeneticallyengineered (转基因的) ones.Severalseedlessfruits, frombananastograpes, arealreadyavailable, buthavemostlyappearedbyluckratherthandesign.Andalthoughthereareafewseedlessvarietiesoftomatoes, theyvetakenresearchersmanyyearstocreate.Nowitcanbedoneveryquickly, asKeishiOsakabeatTokushimaUniversityinJapanhasshown.HisteamusedtheCRISPRgeneeditingtechnologytomakefruitsdevelopeventhoughnoseedshadbeguntoform.“Wehaventtastedthemyet, butintheorytheyshouldtastethesame,”saysOsakabe.Therehavebeenafeweffortstocreateseedlesstomatoesusingearliergeneticengineeringtechniques.ThesemethodstakelongertimecomparedwithCRISPR.Some“seedless”fruitsjusthaveverysmallseeds, andstillrequirepollination (授粉).Butcompletelyseedlessfruitsliketheeditedtomatoesdonotrequirepollinationatall.Suchplantscouldimprovefoodsecuritybyreducingourrelianceonsmallerbeepopulations, saysSaulCunninghamattheAustralianNationalUniversity.Manyfruitgrowersbuybeestopollinatetheircrops.Thereisadeficiencyforfarmers, however.Seedlessplantsusuallyhavetobegrownfromcuttings, whichinvolvesmorelaborthanplantingseeds.CRISPRcouldbeusedtodevelopothertypesoffruitthatdontrequirepollinators, aswellasintroducebeneficialmutations (突变), saysOsakabe.Buttomakeitontothesupermarket, geneeditedplantsmayhavetomeetthesamestandardsasgeneticallyengineeredplants, whichwouldgreatlyincreasecosts.Somearguethatsincegeneeditingisusedtointroducemutationsalreadyfoundinsomeoftheplantsweeat,itshouldnotrequiresuchstrictregulations.1Whathasbeentheproblemwithseedlesstomatoescreatedinthepast?ATheirtastewasnotverygood.BTheystillhadafewbigseeds.CTheirgenescouldnotberecognized.DTheytookquitealongtimetocreate.2WhatdidKeishiOsakabesteamdo?ATheyeditedtomatoesgenes.BTheychangedthetasteoftomatoes.CTheymadeseedlessbananasandgrapes.DTheycreatedgeneticallyengineeredtomatoes.3WhyisCRISPRbetterthanpreviousmethods?AItwillstillrequirepollination.BItwillremainunaffectedwithoutbees.CItwillreducepeoplesrelianceonfoodsecurity.DItwillmakemanygrowersbuybeesforpollination.4Whatdoestheunderlinedword“deficiency”inParagraph7probablymean?ADanger.BDisadvantage.CBenefit.DSolution.B2021山西省高三第一次测试MorethanhalfofworkingAfricanshavejobsinagriculture, butinadequatetoolsandalackofinvestmenthaveleftthecontinentsmostlysmallfarmsstrugglingtofeedagrowingpopulation.Now, awaveoftechnologicalsolutionsisaimingtohelp.EstherUsman, fromKadunaState, NorthwestNigeria, hasbeengrowingcornsinceshewas17, whenshedroppedoutofschooltosupportherfamilyafterherfathersdeath.Twodecadeson, shewasstruggling.Sheoftenlayawakeatnightworryingabouthowtofeedandeducateherchildren.Attimes, moneyransolowthatshewasforcedtosellhercropforabit.“Ifmyfarmwasaffectedbypests, Icouldonlyaffordtobuyasmallamountofpesticide, whichwasusuallynoteffective.Andcorninstorageisoftenlosttomoisture (潮气) andpests, whichisabigproblem,”saysUsman, now38.In2017, UsmanjoinedBabbanGona, asocialenterprisethatactsasafarmerspartnerandoffersfarmerscredit, trainingandothersupport.Itwaslaunchedin2012with102farmers, andnowworkswith20,000.FieldofficersemployedbyBabbanGonaphotographitsfarmersfields.Anappreviewsthephotos, evaluatingthegermination (发芽) rateandseeingifthesoilneedsnutrientsbasedonleafcolors.Thefieldofficersstepintowarnfarmersofanyproblemstheyfindandadviseonpossiblesolutions.Somefarmershaveincreasedtheiryields (产量) by50percent.Oncethecornisharvested, BabbanGonastoresitinsealedcontainersandaimstosellitattherighttimetomaximizethefarmersprofits.ThepaymentsUsmanreceivesfromBabbanGonaallowhertoinvestinacow, tobuynewclothesforherfamily, andtobuildahouse.5WhatcanUsmanbedescribedinherearlylife?AActivebutunskilled.BResponsibleandwise.CHardworkingbutpenniless.DPainedandunambitious.6WhatwasthechallengeforUsmanafterharvestingcorn?ASellingit.BReservingit.CKillingpestsonthefarm.DFeedingandeducatingherchildren.7HowdothefieldofficersworkinBabbanGona?ATheyevaluatethephotosofcrops.BTheylendmoneytoneedyfarmers.CTheysendphotostakenbyfarmerstoanapp.DTheyserveasabridgebetweenfarmersandit.8Whatdoesthetextmainlytalkabout?ATechnologyhelpsAfricanfarmerslivebetter.BAcompanysupportsAfricanfarmers.CFarminginAfricaisfacedwithadifficultsituation.DAfricanfarmersinventsmartfarming.七选五2021武汉市高中毕业生供题Ithadlongbeentroublingalittleboythathisdeskmatecouldrank1stintheclasseverytimewhilehefailedto: heonlyranked21st.Athome, heaskedhismom, “Mom, amImorestupidthanothers? IfeelIamashardworkingashim, buthowcomeIalwaysfallbehind?”_1_Inanothertest, theboyranked15th, andhisdeskmateremained1st.Backhome, heraisedthesamequestion._2_However, wasthisanswerinhersonsbes
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