1、Unit 2Cloning话 题 导 读导语：大家对于克隆这一话题并不陌生，但是到底什么是克隆，如何才能够进行克隆等细节性问题对于大部分人来说还是很神秘的。What is CloningHave you ever wished you could have a clone of yourself to do your homework while you went out to play with your friends？Imagine if you could really do that,where would you start?What exactly is cloning?Clon
2、ing is a way of making an organism(有机体)that is an exact genetic(基因的)copy of another.This means that every single bit of DNA is the same between the two!You might not believe it,but there are human clones among us right now.They werent made in a lab,though.Theyre identical(同样的)twins,created naturally
3、.Below,well see how natural identical twins relate to modern cloning technologies.How is cloning done?You may have first heard of cloning when Dolly the sheep showed up on the scene in 1997.Cloning technologies have been around for much longer than Dolly,though.How does one go about making an exact
4、genetic copy of an organism？There are a couple of ways to do this:artificial embryo twinning(人工胚胎双生)and somatic cell nuclear transfer(体细胞核移植).How do these processes differ?1Artificial Embryo TwinningArtificial embryo twinning is the relatively lowtech version of cloning.As the name suggests,this tec
5、hnology mimics the natural process of creating identical twins.2Somatic Cell Nuclear TransferSomatic cell nuclear transfer(SCNT),uses an approach different from artificial embryo twinning,but it produces the same result:an exact clone,or a genetic copy,of another.This was the method used to create D
6、olly the sheep.Section Warming Up&Prereading&ReadingComprehending练读文 记词汇 学翻译1 教材助读先读通CLONINGWHERE IS IT LEADING US？Cloning has always been with us and is here to stay.It is a way of making an exact copy of another animal or plant.It happens in plants when gardeners take cuttings from growing plants
7、to make new ones.It also happens in animals when twins identical in sex and appearance are produced from the same original egg.The fact is that these are both examples of natural clones.Cloning has two major uses.Firstly，gardeners use it all the time to produce commercial quantities of plants.Second
8、ly，it is valuable for research on new plant species and for medical research on animals.Cloning plants is straightforward while cloning animals is very complicated.It is a difficult task to undertake.Many attempts to clone mammals failed.But at last the determination and patience of the scientists p
9、aid off in 1996 with a breakthrough the cloning of Dolly the sheep.The procedure works like this：1 Female sheep A provides an egg cell.2 The nucleus is removed from the egg cell.3 The egg cell is ready for a new nucleus.4 Female sheep B provides a somatic21 cell for the clone.The nucleus of this cel
10、l contains all the genes needed to produce a new sheep22.5 The nucleus is taken out of the somatic cell.6 The nucleus from sheep B and the egg cell from sheep A are joined using electricity23.7 The cell divides and grows into an embryo24.8 The embryo is put into female sheep C,who becomes the carrie
11、r25 of the clone26.9 The lamb is the clone of the donated27 cell from Sheep B which provided the nucleus28.On the one hand29，the whole scientific world followed the progress of the first successful clone,Dolly the sheep.The fact that she seemed to develop normally30 was very encouraging.Then came th
12、e disturbing news that Dolly had become seriously ill31.Cloning scientists were cast down32 to find that Dollys illnesses were more appropriate to33 a much older animal.Altogether34 Dolly lived six and a half years,half the length of the life of the original sheep.Sadly the same arbitrary35 fate36 a
13、ffected other species,such as cloned mice.The questions that concerned all scientists37 were：“Would this be a major difficulty for all cloned animals?Would it happen forever?Could it be solved if corrections38 were made in their research procedure？”On the other hand,Dollys appearance raised a storm
14、of39objections40 and had a great impact41 on the media42 and public imagination.It became controversial 43.It suddenly opened everybodys eyes to the possibility of using cloning to cure serious illnesses and even to produce human beings44.Although at present human egg cells and embryos needed for cl
15、oning research45 are difficult to obtain46，newspapers wrote of47evil leaders hoping to clone themselves to attain48 their ambitions49Religious leaders also raised moral 50 questions.Governments became nervous and more conservative51.Some began to reform their legal systems and forbade52 research int
16、o human cloning,but other countries like China and the UK,continued to accumulate53evidence of the abundant medical aid that cloning could provide54.However,scientists still wonder whether cloning will help or harm us and where it is leading us55.再记住exact/Izkt/adj.精确的；准确的make a copy of(copy)复制of mak
17、ing.作way的定语。cutting/ktI/n.剪枝；剪报；剪纸twin/twIn/n.双胞胎之一；孪生儿之一adj.成对的；成双的identical/aIdentIkl/adj.同一的；一模一样的The fact is that.中，that引导表语从句。all the time 一直commercial/kml/adj.商业的；贸易的quantities of“大量的”；修饰可数名词复数或不可数名词。straightforward/streItfwd/adj.简单的；直接的；坦率的while在此表示“而，却”，是并列连词，表示对比关系。complicated/kmplIkeItId/a
18、dj.复杂的；难懂的undertake/ndteIk/vt.(undertook,undertaken)着手；从事；承担不定式短语to undertake作定语，修饰task。不定式短语to clone mammals作定语，修饰attempts。Firstly.Secondly.at last.“首先其次最后”，表示论述顺序。pay off 得到好结果；取得成功；偿清breakthrough/breIkru/n.突破procedure/prsid/n.程序；步骤；手续nucleus/njuklIs/n.原子核；中心remove.from.将从移走21 somatic/smtIk/adj.躯体
19、的；肉体的；细胞体的22 过去分词短语needed to.作定语，修饰genes。23 现在分词短语using electricity作方式状语。24 embryo/embrI/n.胚；胚胎；萌芽时期25 carrier/krI/n.携带者；搬运工；运输工具26 who引导非限制性定语从句，修饰先行词female sheep C。27 donate vt.捐赠；捐献28 which引导定语从句，修饰Sheep B。29 on the one hand.一方面30 that she seemed to develop normally是fact的同位语。31 Then came the dist
20、urbing news that.中，then位于句首引起完全倒装。本句中的news与that Dolly had become seriously ill是同位关系。32 cast/kst/vt.(cast，cast)扔；投；掷cast down 使失望；使沮丧33 be appropriate to 适合于的；与相称的34 altogether/lte/adv.总共；完全地35 arbitrary/bItrrI/adj.任意的36 fate/feIt/n.命运；天命37 that引导的定语从句，修饰the questions。38 correction/krekn/n.改正；纠正；修正39
21、 a storm of常形容感情的爆发。40 objection/bdekn/n.不赞成；反对；异议object/bdekt/vi.反对；不赞成41 impact/Impkt/n.撞击；冲击；巨大的影响42 medium/midIm/n.(pl.media/midI/)媒介；手段；工具the media大众传播媒体(如电视、报纸等)43 controversial adj.有争议的；引起争议的44 of using cloning.作定语，修饰the possibility。45 过去分词短语needed for cloning research作定语，修饰human egg cells an
22、d embryos。46 obtain/bteIn/vt.获得；赢得47 write of 描写；论及48 attain/teIn/vt.获得；到达(水平、年龄、状况等)49 现在分词短语hoping to clone themselves.作定语，修饰evil leaders。50 moral/mrl/adj.道德(上)的；伦理的51 conservative/knsvtIv/adj.保守的；守旧的52 forbid/fbId/vt.(forbade,forbad,forbidden)禁止；不准53 accumulate/kjumjleIt/vt.&vi.积累；聚积54 that cloni
23、ng could provide是that引导的定语从句，修饰先行词medical aid。that在从句中作provide的宾语。55 whether和where分别引导宾语从句，均作wonder的宾语。再翻译克隆：它将把我们引向何方？克隆一直与我们同在，而且它还要持续下去。这是一种用来生产与原型完全相同的动植物的方法。当园艺师从生长着的植物上剪下枝条来培植新植物时，就会产生这种现象。这种现象也发生在动物身上，从同一个原生卵子产生性别和相貌相同的双胞胎也是克隆。实际上，这些都是自然克隆现象的例子。克隆技术有两个主要用途。第一，园艺师一直用它生产大量的商用植物；第二，它在对新植物物种的研究以及
24、对动物的医学研究方面都是有价值的。克隆植物简单，但克隆动物就非常复杂了。这是一项很难完成的任务。克隆哺乳动物的多次尝试都失败了。但是决心和耐心使科学家们最终于1996年收获了突破性的结果克隆羊“多莉”。它的程序如下所示：1 母羊A提供一个卵细胞。2 将卵细胞中的细胞核取出。3 卵细胞准备接受新的细胞核。4 母羊B提供一个供克隆的体细胞，该细胞的细胞核包含生产一头新羊所需要的全部基因。5 取出该体细胞的细胞核。6 用电将母羊B的体细胞核和母羊A的卵细胞结合起来。7 细胞分裂并生长成胚胎。8 把胚胎置入另外一头母羊C体内，母羊C就是克隆羊的代孕。9 这头小羔羊就是由提供细胞核的母羊B所提供的细胞克
25、隆而成的。一方面，整个科学界都在关注着首例成功的克隆动物多莉羊的成长。多莉羊看起来是在正常地成长的事实很令人鼓舞。接着传来了多莉病重的坏消息。研究克隆的科学家们发现多莉得的病更容易发生在年老的羊身上，这让他们很沮丧。多莉总共存活了六年半，这是它的原型羊寿命的一半。可悲的是，同样无法控制的命运也在影响着其他物种，如克隆鼠。所有科学家们都关心的问题是“这是不是所有克隆动物的一个主要困难呢？这种现象会不会永远发生？如果改进他们的研究程序，问题会不会解决呢？”另一方面，多莉的出现引起了一阵强烈的反对，对媒体和公众的想象力也产生了极大的影响。它引起了争议。它突然打开了人们的眼界，使人们看到了有可能利用克
26、隆技术来治疗重病，甚至还有可能克隆出人类。尽管目前供克隆研究的人类卵细胞和胚胎很难获得，报纸上报道说，有些邪恶的头目希望把自己克隆出来以实现他们的野心。宗教领袖也提出了道德方面的问题。各国政府变得惶恐不安而且更加谨慎。有些政府开始改革他们的司法制度，明令禁止进行克隆人类的研究，但是其他国家，如中国和英国，则仍然在继续收集克隆技术有可能提供大量医疗救助的证据。然而，科学家们仍对克隆技术有助于人类还是有害于人类，以及克隆技术将把我们引向何方感到困惑。通语篇 学理解 重分析2语篇理解Step 1 Fast Reading1Read the text quickly and complete its
27、main idea.The text is mainly about the _ of animal cloning and the life of Dolly the sheep，as well as the reasons why cloning is still _.procedurecontroversial2Read the text and then find the main idea of each paragraph.Para.1AThe effect of Dolly.Para.2 BThe major uses of cloning.Para.3 CPeoples rea
28、ction to cloning.Para.4 DThe definition(定义)of cloning.Para.5EThe problem of Dolly.答案：15 DBEACStep 2 Careful Reading(一)Read the text and then choose the best answer according to the text.1It can be inferred from the passage that a cloned animal _.Ausually lives as long as the original oneBusually liv
29、es longer than the original oneCusually dies earlier than the original oneDis usually as healthy as the original one2Which of the following is an advantage of cloning?ACloning can be used for earning money.BLarge quantities of food can be produced by cloning.CCloning can not help keep animals from b
30、ecoming extinct.DFamous persons who have passed away can be cloned.3We can use the skill of cloning to _.Abring about global peaceBcreate other famous scientistsCimprove the development of learning languageDcure some special diseases4What can we learn from the text?ACloned mice can live as long as t
31、he original ones.BCloning will come to an end because of objections.CAll the researches into human cloning will be forbidden.DIt is more difficult to clone animals than clone plants.答案：14 CBDD(二)Fill in the blanks.Cloning：Where is it leading us？DefinitionCloning is a way of making a(n)1._ of another
32、 animal or plant.Major uses of cloningGardeners use it to produce 2._ quantities of plants.It is valuable for research on new plant species and for 3._ research on animals.exact copycommercialmedicalAbout Dolly the sheepEncouraging news：Dolly developed 4._.Disturbing news：Dolly became seriously 5._
33、and lived six and a half years,half the length of the life of the 6._ sheep.normallyilloriginalArguments over cloningNewspapers wrote of 7._ hoping to clone themselves to attain their ambitions and religious leaders raised 8._ questions.Some governments 9._ research into human cloning while others c
34、ontinued to accumulate.10._ of the abundant medical aid that cloning could provide.evil leadersmoralforbadeevidence(三)Analyze the following difficult sentences in the text.1It also happens in animals when twins identical in sex and appearance are produced from the same original egg.分析翻译 这种现象也发生在动物身上
35、，从同一个原生卵子产生性别和相貌相同的双胞胎也是克隆。后置定语2Cloning plants is straightforward while cloning animals is very complicated.分析 Cloning plants 和 cloning animals 在句中都充当主从句的_；while 意为“而，然而，却”，是并列连词在句中起对比、比较的作用。翻译 克隆植物简单，但克隆动物就非常复杂了。主语3Then came the disturbing news that Dolly had become seriously ill.分析翻译 接着传来了多莉病重的坏消息。同位语4Although at present human egg cells and embryos needed for cloning research are difficult to obtain,newspapers wrote of evil leaders hoping to clone themselves to attain their ambitions.让步目的状语后置定语后置定语翻译 尽管目前供克隆研究的人类卵细胞和胚胎很难获得，报纸上报道说，有些邪恶的头目希望把自己克隆出来以实现他们的野心。