大学英语综合教程3unit8答案解析

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1、Unit8PartIPre-ReadingTaskScriptfortherecording:ACloneofOurOwnWillhumansbethenextclones?Thetechnologystillhasalongwaytogobeforeit'sconsideredsafetotryonhumans.Butevenifitweresafe,woulditberight?Let'shearwhatProfessorHankGreelyofStanfordUniversityhastosayonthis

2、topic.Interviewer:Whenwillwecloneahuman?Greely:That'snotasimplequestion.Ithinkwehavetoaskourselves:istheresomethingaboutthetechnologythatissowrongorsoevilthatitshouldn'tbeusedatall?Orshoulditbejudgedaccordingtoitsintendeduses?Interviewer:Whatareacceptableuses

3、?Greely:Wereallyneedtodistinguishbetweendifferenttypesofcloning.Ifweusecloningtogrowanewliver,Idon'tthinkmanypeoplewillhaveproblemswiththat-aslongasit'sgrowingaliverandnottakingaliverfromaclonedperson.Humanreproductivecloningismuchtrickier.Interviewer:Why?Gre

4、ely:Safety.There'sstillaverylowsuccessrate.WithDolly,thefirstclonedlamb,29treatedeggswereimplantedinsheeptogetoneDolly.Wedon'tworrytoomuchaboutsheepmiscarriagesoraboutdeformedlambsbeingborn.Butwewouldwithhumans.Andwewouldn'tknowifahumanclonewouldbehealthy.Int

5、erviewer:Dollyappearstobehealthy.Whywouldn'tahumanclonebeso?Greely:Theremaybecellchangesthatareinitiallyinvisibleandonlyshowthemselvesasthecloneages.There'salsoaproblemwiththeendsofchromosomesincells,whichshortenuntilthecellscannolongerreproduce.WeknowthatDol

6、ly'schromosomesareshorterthanthoseofothersheepherage,andwedon'tknowwhatthatmeansyet.-188-AppendixIInterviewer:Supposehumancloningwassafe.Inwhatsituationsdoyouseecloningbeingused?Greely:Helpingparentswhoarehavingdifficultyhavingchildrenwouldbeonearea.Interview

7、er:Arethereothersituationswhereitmightbeacceptabletocreateahumanclone?Greely:Asituationwhereparentswanttocreateanewchildtobeabonemarrowdonorforanoldersickchild.That'sarealtoughone.Butthatissuemightneverariseifwesucceedingrowingbonemarrowoutsidethebody.Another

8、situationiscloningachildwhohasaccidentallydied.Ithinkthat'sdisturbing.ButI'veneverbeeninthatpositionandsoIdon'tfeelcomfortablesayingwhetherthat'sagoodapplicationorabadapplicationofthetech