河北省武邑中学高考英语一轮复习 Unit2 Cloning导学案 新人教版选修8.doc

河北省武邑中学2016届高考英语一轮复习 unit2 cloning导学案 新人教版选修8readingcloning: where 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 to make new ones. it also happens in animals 1._ 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. secondly, it is valuable for research on new plant species and for medical research on animals. cloning plants is straightforward 2._ cloning animals is very complicated. it is a difficult task 3._ (undertake). many attempts to clone mammals failed. but at last the determination and patience of the scientists paid 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 somatic cell for the clone. the nucleus of this cell contains all the genes needed to produce a new sheep.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 electricity.7. the cell divides and grows into an embryo.8. the embryo is put into female sheep c, who becomes the carrier of the clone.9. the lamb is the clone of the donated cell from sheep b which provided the nucleus.on the one hand, the whole scientific world followed the progress of the first successful clone, dolly the sheep. the fact that she seemed to develop normally was very 4._ (encourage). then came the disturbing news 5._ dolly had become seriously ill. cloning scientists were cast down 6._ (find) that dollys illnesses were more appropriate to a much older animal. altogether dolly lived six and a half years, half the 7._ (long) of the life of the original sheep. 8._尽管 her problems, dolly successfully produced a lamb in a 9._ (nature) birth. sadly the same arbitrary fate affected other species, such as cloned mice. the questions that concerned all scientists were: “would this be 10._ major difficulty for all cloned animals? would it happen forever? could it be solved if corrections were made in their research procedure?”on the other hand, dollys appearance raised a storm of objections and had a great impact 11._ the media and public imagination. it became controversial. it suddenly opened everybodys eyes to the possibility of using cloning to cure serious illnesses, 12._ even to produce human beings.although at present human egg cells and embryos needed for cloning research are difficult 13._ (obtain), newspapers wrote of evil leaders hoping to clone themselves to attain their ambitions. religious leaders also raised moral questions. governments became nervous and more conservative. some began to reform their legal systems and 14._ (forbid) research into human cloning, but other countries like china and the uk, continued to accumulate evidence of the abundant medical aid that cloning could provide. however, scientists still wonder whether cloning will help or harm us and where it is leading us.*pick out 15 new words and translate them into chineseusing language:the return of the dinosaurs?the 1._ (possible) of cloning fierce and extinct wild animals has always excited film makers. and they are not the only ones! the _2._ (popular) of films such as jurassic park, in which a scientist clones several kinds of extinct dinosaurs, proves how the idea struck a mixture of fear and excitement into peoples hearts. but in fact we are a long way from 3._ (be) able to clone extinct animals. scientists are still experimenting with cloning mammals. this is because the cloning of mammals is still a new science and its story only began seriously in the 1950s as this list shows:1950s cloning of frogs1970s research using the embryos of mice1979 work on embryos of sheep and mice1981 first experimental clones of mice1983 first experimental clones of cows1996 first clone of a mammal: dolly the sheep2000 cow gave birth to a bison2001 chinas first cloned twin calves2002 first cloned cats2005 first cloned dogfrom time to time people suggest that extinct animals like dinosaurs, can possibly 4._ （bring） back to life through cloning. 5._ (fortunate), with what we know now, this is either impossible _ unsuitable. there are many reasons.the initial requirement is that you need perfect dna which gives information for how cells are to grow.all efforts of cloning an animal will be in vain if there is not enough diversity in the group to overcome illnesses. diversity in a group means having animals with their genes arranged in different ways. the advantage is that if there is a new illness some of these animals may die, others will survive and pass on the ability to resist that disease to the next generation. the great drawback to cloning a group of animals is that they would all have the same arrangement of genes and so might die of the same illness. then none of them would be left to continue the species.it would be unfair to clone any extinct animals if they were to live in a zoo. a suitable habitat would be needed for them to lead a natural life.6._ (base) on what we know now, you cannot clone animals that have been extinct longer than 10 000 years. actually, dinosaurs disappeared 65 000 000 years ago. so the chance of dinosaurs ever returning to the earth is 7._ (mere) a dream.归纳：1.extinct _ 2.initial _ 3. diversity _4. resist _ 5. drawback_ 6.habitat _ 7.species_ 8 in vain _9. pass. on to. _ 10. 总结with的复合结构_重点单词用法1. differ （vi）不同；相异； 1) humans differ from other mammals in their ability to speak. 人与其他哺乳动物的不同之处在于人能说话。【differ from .与不同】2) the two sides differ with each other over the question of pay.【about/ on/ over sth. 关于】 3) thats where we differ. 那就是我们意见不合的地方。 4) it doesnt make any difference to me whether you go or not. 【make a difference 有影响】2. undertake v. undertook (pp.) undertaken（pt.）she undertook full responsibility for the new changes. 承担he undertook to pay the money back in six months. 承诺3. cast v./n cast (pt) cast（pp） 扔，投，掷1) she cast a glance in his direction. 瞥一眼the tree cast a long shadow on the grass. 投下阴影 2) dont be so cast down. just keep up your spirits. 沮丧4. object v. 反对 we object to being treated like this. 反对 they objected that the schedule was too tight. 反对说 n. whats that dark object lying in the street? 物体 his one object in life is to earn as much money as possible.目的【拓展】objection n. raise an objection 提出反对意见5. obtain v.(通过努力等)获得，得到；买到：at oxford, he obtained his masters degree in electrical engineering.we wished to obtain first-hand information.6. forbid v. forbade(pt.) forbidden,(pp.) 禁止1) the city forbids keeping dogs. 2) i forbid you to tell anyone about the secret.3) he forbade his children sweets because he didnt want their teeth to be ruined.4) women are forbidden from going out without a veil in arabian countries. 7. owe v. 1) he owes his father 50 yuan / 50 yuan to his father. 欠2) i owe him an apology. i owe an apology to him. 应向.道歉3)these early settlers owed their survival to hard work and determination to succeed.把.归功于i owe it to you that i finished my work in time. it为形式宾语 4) owing to the rain, they could not come. 由于9. bother v.im sorry to bother you, but could you tell me the way to the station? 麻烦i need to advertise for a roommate. -why bother? mary is interested. 别费劲，没有必要10. strike v.struck (pt.) struck (pp)1) the stone struck me on the forehead. 击中 2) it suddenly struck me that we could use a computer to do the job. 突然想到3) he was struck by the beauty of the girl. 打动4) the clock has just struck twelve. （钟）敲响5) she struck a match. 划（火柴）6) the workers are striking for better working conditions. 罢工n. the whole staff were on strike. 短语用法1. pay off 【读句子，猜词义】 ive just paid off my loan from this bank. did your plan pay off?all those weeks of studying will pay off when you take the exam. 【拓 展】 pay back pay for .典型句式1.it suddenly opened everybodys eyes to the possibility of using cloning to cure serious illness and even to produce human beings. 翻译：_2 it is a way of making an exact copy of another animal or plant. 精确的【拓展】to be exact .确切地说1) thats _what i expected. 那正是我希望的.2) - people should stop using their cars and start using public transport. - _. the roads are too crowded as it is. （2005浙江） 【正是如此】 a. all right b. exactly c. g