新视野大学英语听说教程第四册unit8.docx

新视野大学英语听说教程第四册unit8.docx

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新视野大学英语听说教程第四册unit8

Uint8

II.BasicListeningPractice

Script                                                                             

M:

Scentistsclaimtheworldpopulationhas99.5%ofthesameDNA.

W:

Butthisdoesn’ttellusthereisnosuchthingasrace.

Q:

WhatistrueoftheDNAofdifferenceraces?

Script

W:

Withtheadventofthegeneticmapweknowwhereeverythingis,butdoweknowwheretogowithit?

M:

Yourmapseemstodifferlargelyfrommygeographicalmap!

Q:

Whatdoesthemanimply?

Script

M:

Asyouknow,ithastakenmillionsofyearsofevolutionandnaturalselectiontogetuswherewearetoday.

W:

Yes,butnowthatwehavegeneticengineering,weseemtohavedecidedthatwewanttobeGod.

Q:

Whatdoesthewomanimply?

Script

M:

Ithinktheresearchintocloningwillleadusintodangers,fillinguswithfalsehopesofperfection.

W:

It’stoolatetoturnbacktheclock.We’lljusthavetodependoncommonsensetosolveuncommonproblems.

Q:

Whatdoesthewomanmean?

Script

W:

InAmerica,manyprisonersarehavingtheircasesreviewed,andsomehaveevenbeenfreedthroughDNAtesting.

M:

Exceptfortheoneswhosedeathsentencehasalreadybeencarriedout.

Q:

WhatcanwelearnaboutDNAtestingfromthedialog?

Keys:

1.B 2.C 3.D 4.A 5.C

III.ListeningIn

Task1:

StemCellResearch

Script

Gregory:

TheRepublicanpartyinAmericaisopposingstemcellresearch.Ifindit

      hardtobelievethatinthisdayandage,someonewoulddothat.

Lillian:

Stemcellresearchsoundsprettyimpressive,I’lladmit.Butjustwhatisit?

Gregory:

Well,astemcellisaspecialtypeofcell.Itisageneralcellthat,whenit

      devides,canbecomeanyspecifictypeofcell.

Lillian:

Youmean,astemcellcanbecomeaheartcell?

Orabrainorakidneycell?

Gregory:

That’saboutit.Stemcellsareapartofthebody’smaintenanceandrepair

      system.Whentheydivide,theycanbecomeanycelltype.

Lillian:

Iguesstherewouldbesometremendousmedicaladvantagesinthatsortof

     research.

Gregory:

You’vesaidamouthful.Recently,scientistswereabletohelpamanwho

      lostajawboneforcancer.Theyrecreatedbonematerialforhisjawfromstemcells.Whatitmeansisthatsincethenewbonewascreatedoutoftheperson’sowncells,therewasnoproblemwithrejectionbecausetheDNAwasthesame.

Lillian:

Ibetthepersonwasdelighted.Whywouldanyoneopposethatsortofresearch?

Itwouldseemtohaveendlesspotentialtobenefitthehumanrace.

Gregory:

Iagree,buttherearepeoplewhothinkweshouldnotinterferewithnatureandmanipulate“whatisnatural”.

Lillian:

It’seasiertoholdsuchanarrowviewifyou’renotinapositiontoneedthebenefitsoftheresearch.Ifyou’remissingajawbonebecauseofcancer,youprobablysupporttheresearch.

Whatisthepassagemainlyabout?

Whoisagainststemcellresearch?

Whatisspecialaboutastemcell?

Whencanastemcellbecomeanothercelltype?

Accordingtothepassage,whydosomepeopleopposestemcellresearch?

Keys:

1.B 2.A 3.A 4.A 5.D

Task2:

TheImprovementofRice

Script      

Scientistsnowknowalotmoreaboutagrainthatpeoplehaveeatenfortenthousandyears.（S1）Researchteamsaroundtheworldhavecompletedamapofthe（S2）genesofrices.Thefindingsappearedlastweekinthe（S3）journalNature.

Theaimistospeeduptheimprovementofrice.Thescientists（S4）warnthatthekindsofriceplantsusednowhavereachedthelimitoftheir（S5）productivity.Yetworldriceproductionmust（S6）growbyanestimated30percentinthenexttwentytomeetdemand.By2025,asmanyas4.6billionpeoplewilldependonricefor（S7）survival.Thereisalotofpressureonbreederstoimprovethecrop,andthericegenomeisavaluabletooltodothat.（S8）Plantbreedershavealreadyusedpreliminaryinformationfromthericegenometocreateexperimentalstrainsofricethatbetterresistcoldandpests.

Theresearchersalsosayriceisanexcellentchoiceforgeneticmappingandengineering.Ricegeneshaveonlyabout390millionchemicalbases.Thatmaightsoundlikealot.Butothermajorfoodgrainshavethousandsofmillions.（S9）Thenewmapcouldbetterexplainmorethanjustrice.Ricesharesacommonancestorwithothercerealcrops.Becausericeisthefirstcerealcroptobefullyanalyzed,researchersexpectthatsufficientknowledgeofitsgeneticinformationwillrevealtheheredityofmorecomplexgrains,includingcorn,wheatandbarley.

（S10）Whilesignificantprogresshasbeenmadeintheanalysisofthericegenome,themappingofhumangenesisalsomakingheadway.Whenscientistscanidentifyandmanipulategenesthatcausecertaindiseases,mankindwillcurethemeasily.Thehumangeneticmapmayhelpuscontrolaperson’sheight,weight,appearanceandevenlengthoflife.

Task3:

TheFirstClonedCat

Script

Intheage-oldbattleofcatsanddogs,scoreoneforthecats.ResearchersatTexasA&MUniversityrecentlyannouncedthattheyhavesuccessfullyclonedacatnameRainbow—thefirstpetevercloned—afterseveralyearsofunsuccessfuleffortstocloneadognameMissy.

Theork,financedbyacompanyhopingtoprovidepet-cloningservicestowealthyowners,addscatstoagrowinglistofsuccessfullyclonedanimalsthatincludespigs,sheep,cattleandmice.

Thesuccessdemonstratescloningisatechnologythatcouldbetransferredtootheranimalfamiliesaswell.Theaccomplishmentmayprovidenewtoolsforstudyingdiseasessuchascats’AIDS,avaluableresearchmodelforAIDSinhumans.

Researchintoanimalcloningremainsanimportantscientificalternativeuntiltheissueofhumancloningissettled.Andthatseemsunliklyintheimmediatefuture,foritinvolvesreligiousandmoralprinciples.Thereare,forexample,groupsthatinsistnooneshouldbeallowedtotakeontheroleofGodtheCreator.

Tocreateclonedcatembryosfortheexperiment,researcherstransferredDNAfromadultcatcellsintoeggcellsstrippedoftheirowngeneticinformation.Outof82attemptswithclonedembryos,oneattemptresultedinafailedpregnancy,andanotheryieldedakittennamedCC,deliveredfromasurrogatemotheronDecember22.Thekitten’snamerefersto“CarbonCopy”and“Copycat”,thenameofthecloningproject.

Cloningattemptswithdogshaveprovenunsuccessfulinpartbecausedogs’reproductivecyclesaremorecomplicated.

ThetechniquemayalsoworkwithendangeredcatssuchastheAfricanwildcat,fishingcatandblackfootedcat.

Ironically,theincreasedknowledgeofcatreproductionmaybestbesuitedfordevelopingcatcontraceptivestocontroltheU.S.catpopulation.

1.Whichofthefollowingwouldbethebesttitleforthepassage?

WhatdidresearchersatTexasA&MUniversityrecentlyannounce?

WhichanimalsareNOTmentionedinthepassageashavingbeencloned?

Accordingtothepassage,whyishumancloningunlikelytohappeninthenearfuture?

Whatdoesthepassagesayaboutthepregnancyandbirthincatcloning?

Keys:

1.A 2.B 3.C 4.B 5.C

IV.SpeakingOut

MODEL1  Whyarepeopleprotestingagainst

            geneticallymodifiedfoods?

Susan:

Withsomanypeoplesufferingfrommalnutritionaroundtheworld,whyarepeopleprotestingagainstgeneticallymodifiedfoods?

Chris:

Somepeopleareprotestingaboutgeneticallymodifiedfoods,butevenmorepeopleareprotestingthefactthatprocessedfoodscontainingtheseingredientsaren’tlabeled.

Susan:

Butwhyshouldtheybelabeled?

Chris:

Noteveryoneissurethatgeneticallymodifiedfoodsaresafe.Theywanttobecertainthatbiotechfoodshavethesmecompositionasorganicfoods.

Susan:

Buttherearemoreurgentproblemsinthisworld.Manypeoplearedyingofstarvation.

Chris:

Butthosewhoaren’tstarvingmaywantgeneticallymodifiedfoodstobelabeledsotheyknowwhatfoodstheyshouldanddshouldn’teat.

Susan:

Youknow,Iheardofageneticallymodifiedfishthatgrewtobetentimesitsnormalsize.

Chris:

Thatsuresoundsabnormal.

Susan:

Yeah,itdoessoundabitstrange,butthatfishcouldfeedtentimesasmanypeople.

Chris:

You’reright;geneticallymodifiedfoodmighthelpsolveworldhunger.ButIthinkwehavearighttoknowwhatweareeating.

MODEL2  Doyouthinkthecloningofhumans

           shouldbeforbiddenbylaw?

Script

Susan:

AfterthecloningofDollythesheep,Ithinkhumancloningisnext.

John:

Whoa.Ihavesomereservationsaboutit.Therearestllmanyscientificproblems 

    tosolvebeforehumancloningstarts.

Susan:

There’saneasierway.TheClonaidCompanysaysthey’veclonedhumans.

John:

Oh,myGod!

Theseguysclaimaliensfromanotherplanettaughtthemhuman

cloning.

Susan:

Awomangavethemhalfamilliondollarstocloneherdeaddaughter.

John:

Clearlythatwomandoesn’tknowmuchaboutcloning.Howriskyitis!

Susan:

Iknowit’sinefficient.Ittook276triestoproduceDolly.Butwhyisitrisky?

John:

Clonedanimalsgrowabnormallylargeandageunnaturallyfast.

Susan:

Inotherwords,thatwomanmaynotbehappywithhercloneddaughter.

John:

Thentherearetheemotions.Nooneknowsifcloningdamagesthemind.

Susan:

Doyouthinkthecloningofhumansshouldbeforbiddenbylaw?

John:

Tomymind,thecloningofhumanorgansshouldn’tbeprohabited.Itmayhelp 

    solvemedicalproblems.

Susan:

Iseeyourpoint:

cloningshouldberegulatedifit’stobenefithumanity.

MODEL3  Isitinterferingwithnature?

Script

Nora:

Somereligiousgroupsareopposedtogeneticresearch.Theybelieveit’sinterferingwithnature.

John:

Iknow.Butnaturecanbeprettyhard-nosedtoo,soweoftenneedtointerferewithher—webuilddamstocontrolflooding.

Nora:

There’remanydiseasesthatareapart