oneddnacanbeseenashisfather'stwinbrother,onlydelayitfordecadeswasborn.itishardtoimaginewhenapersonfindshimselfisanotherperson'scompletecopiesof,he(she)haveanyfeelings? [editthisparagraph]theoriginofcloning cloningistheenglishtransliterationoftheclone,isasimpleandstress-inducedvegetativepropagationartificialmeans.however,cloningandvegetativepropagationaredifferent.asexualreproductionmeansthatgenderisnotmaleandfemalegermcellsthroughthecombinationoforganismsproducedbyonlyonemodeofreproductionoffuturegenerations,thereisacommonreproductivespores,buddingreproductionandreproductivesplit.byplantroots,stems,leavesandsoonthroughlayering,cuttingsorgrafting,suchasanewentityalsocalledvegetativepropagation.sheep,monkeysandcattleandotheranimalsthereisnomanualoperationisnotcarriedoutthecloning.scientiststoartificialgeneticmanipulationofanimalsandplantsiscalledreproductivecloningprocess,thisiscalledcloningbiotechnology. theideaofcloningembryosbygermanscientistsfirstproposedin1938,andin1952,scientistsusethefrogtocarryoutthefirstcloningexperiments,aftertherepeateduseofanimalcloningtechnologyforresearch.becausethetechnologyisalmostnoprogresshasbeenmade,thestudywasintheearly80'sintothetrough.later,itwasusedforcloningofembryoniccellsinmammalssuccess.july5,1996,britishscientist,dr.ianwilmutofadultsheepbysomaticcellcloningofasheeplivebirthstothestudyofcloningtechnologyhasbroughtamajorbreakthrough,itcanonlybebrokenthroughthepreviousanimalembryoniccellscloningtechnicaldifficulties,thefirstsomaticcellswiththegoalofanimalcloning,toachieveahighersenseofanimalreproduction.thegoalofcloningresearchistofindabetterwaytoalterthegeneticmakeupoflivestock,producetotheconsumergroupsthatmayberequiredtoprovidebetterfoodoranimalofanychemicalsubstances. cloningofthebasicprocessisfirsttocontainthegeneticmaterialofsomaticcellsfornucleartransfertothenucleustotheegginadditiontotheuseofmicrocurrentelectricalstimulation,etc.sothatthetwomergeintoone,andthencelldivisiontopromotethebreedingofthisnewdevelopmentintoembryos,whenembryonicdevelopmenttoacertainextent(roslininstituteclonedsheepusedinabout6days)wereimplantedinanimalsandthenmaketheuterusofpregnantanimalscanbeproducedtoenabletheprovisionofcellswithgenesfromthesameanimal.ifthisprocessforthegenetictransformationofsomaticcells,thenanimalcloninggenerationsofthesamegenechangesoccur.克隆鼠nurturethesuccessofthreegenerationsofthe"honolulutechnique"dollyandcloningtechnology,themaindifferenceisintheprocessofcloningthegeneticmaterialwithoutthecultivationofculturemedium,butdirectlyintotheeggusingphysicalmethods.theprocesstoreplacetheuseofchemicalstimulationofelectricalstimulationtore-controlegg.july5,1998,japan,ishikawaprefecturelivestockcenterandkinkiuniversityscientistslivestocklabannouncedthattheymakeuseofsomaticcellcloningadultanimalsofthebirthoftwocalves.thisisthebirthoftwoclonedcattlecloningofadultanimalsshowthatthetechniqueisrepeatable. whatiscloning? cloningisacloneofthetransliterationofenglishwords,clonederivedfromgreekklone,referstotheoriginalintentofseedlingsoryoungshootstovegetativepropagationorvegetativepropagationmethodsofbreedingplants,suchasstrokeandgraftinserted. today,cloningreferstoorganismscarriedoutthroughsomaticcellcloning,aswellasvegetativepropagationbytheformationoffuturegenerationsofthesamegenotypeofthepopulationofindividuals.cloningcanalsobeinterpretedasareproduction,copy,thatisgeneratedfromtheprototypecopyofthesame,itsappearanceandgeneticallyidenticalwiththeprototype. infebruary1997,sheep"dolly"thenewsofthebirthofthedisclosure,theimmediatecauseofconcernallovertheworld,thisfirstbythebritishbiologistnurturedthroughcloningcloningsheep,meanthathumananimalscanmakeuseofasomaticcell,resultinginaidenticalwiththeanimallife,breakingthelawsofnatureremainunchangedthroughtheages. whatelsecanwecologne? itshouldbesaidthatlifecanbecloned. whathasnowbeencloned? frog:in1962,wasnotsuccessful. lei:1963,chinesescientiststongdizhouearlyin1963byamalecarpcarpgeneticmaterialinjectedintotheeggsoffemalestosuccessfullycloneafemalecarp,thanthecloningofdollythesheepasearlyasthe33years.however,becausetherelevantpapersarepublishedinachinesescientificjournal,hasnottranslatedintoenglish,itisnotknowninternationally.(from:pbs) ancientmythology,themonkeykingintotheirowncountlesssmallhairsofthebizarrestoryofthemonkeykingtoexpresstheyearningofmankindforself-replicationoftheillusion.in1938,germanscientistsfirstproposedtheideaofcloningamammal,in1996,somaticcellclonedsheep"dolly"wasborn,thecloningoftheworldisrapidlybecomingthefocusofattention,peoplecannothelpbutdoubt:wewillnotbeinthebackofsheep?questionsforallofthisfear.however,thenoisyvoiceagainsthumancloninghavenotarrivedinpursuitofscientists,alongwithcattle,mice,pigsandevenmonkeysandhumanbiologicalcharacteristicsthataremostsimilartotheprimateshavebeenclonedsuccessfully,peoplehavebelievedthatoneday,scientistswilluseahumancellreplicationtoprovidecellswiththesamepeoplewho,humancloningisnotthedream << 上一页 [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] ... 下一页 >>
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