【精品】book8 unit2 Cloning精品ppt课件.ppt

book8 unit2 CloningUnit 2 CloningReading TwinsThey are born naturally and identical in sex and appearance.A strawberry plantThe new plants that grow from the runners are exact copies of the original plant.一株草莓依靠它沿地一株草莓依靠它沿地“爬走爬走”的匍匐茎的匍匐茎,一年内就能长出数百株草莓苗。一年内就能长出数百株草莓苗。我国成功繁殖克隆兔我国成功繁殖克隆兔 体形要比普通兔大许多体形要比普通兔大许多2002年年5月月中旬成功地中旬成功地繁殖了一只繁殖了一只胚胎细胞胚胎细胞克隆兔。克隆兔。我国成功繁殖克隆兔我国成功繁殖克隆兔 体形要比普通兔大许多体形要比普通兔大许多2002年年5月月中旬成功地中旬成功地繁殖了一只繁殖了一只胚胎细胞胚胎细胞克隆兔。克隆兔。2005 cloning dogsIn pairs discuss what you understand about cloning.Then list the questions you want to find out.Share your lists with one another.Pre-reading 1.What is a clone?A clone is an animal or a plant produced naturally or artificially from the cells of another animal or plant and is exactly the same as it.2.How is a clone produced？The cloning of plants is simple and relatively easy.It can be done by taking cuttings(man-made cloning)or letting the plant produce its own runners(natural cloning).The cloning of animals is more complicated.It was not achieved until 1996 and is fully explained in the first reading.3.What benefits can humans gain from cloning？Medical cloning can help cure serious illnesses that ruin ones quality of life(such as Parkinsons disease or Alzheimers disease).It can help infertile people have babies.4.What problems may arise when humans are cloned?People may want to clone themselves so they can live forever.People may want to clone dead children.People may want to clone their favourite pets.1.What is the writing style?A.Expositive(说明性的说明性的).B.Descriptive.C.Argumentative(议论性的议论性的).A 2.The main idea of the text is _ A.animal cloning is very valuable and can benefit the world.B.animal cloning could be misused by bad people so it must be forbidden.C.animal cloning is well developed because Dolly the sheep was born.D.animal cloning raised arguments and scientists are not sure about its future.D 3.Dolly the sheep _.A.looked exactly like the sheep that provides the egg.B.was the exact copy of the sheep that provides the nucleus.C.looked like the sheep that gave birth to it.D.had the characteristics of all three sheep.B 4.It can be inferred from the passage that a cloned animal_.A.usually lives as long as the original one B.usually lives longer than the original one C.usually dies earlier than the original one D.is usually as healthy as the original oneC 5.Which of the following is not an advantage of cloning?A.Cloning can be used for medical purposes.B.Large quantities of food can be produced by cloning.C.Cloning can help keep animals from becoming extinct.D.Famous persons who have passed away can be cloned.D 6.Which statement is NOT true?A.Cloning is something that has been developed quite recently.B.Twins that look exactly the same are originally from the same egg.C.Cloning is used by gardeners to make more money.D.Animal cloning is much more difficult than plant cloning.A 7.The cloning of Dolly the sheep succeeded because _.A.its easier to clone a sheep than other animals B.the scientists were determined and worked hard with patienceC.the scientists were rewarded and got lots of moneyD.many other attempts to clone mammals failedB 8.We can infer from the last three paragraphs that _.A.the normal development of Dolly had no effect on the cloning of other species.B.Dollys serious disease and final death disturbed the whole world.C.Dolly successfully cloned a new lamb with the help of cloning scientists.D.there were arguments about animal cloning and concerns about the future of cloning.D True or false:1.People feared that Cloned Hitlers would do harm to the world.2.All the research into human beings will be forbidden.3.Some countries will use cloning in a wise way.Para 5:Peoples reaction to cloningMany governments forbade research into human beings.T T F Careful reading The main idea of each paragraph.1.Cloning is _2._ 2.Cloning has _ uses.3.The _ of Dolly.4.The _ of clonging in society.5.The attitudes towards cloning.a way of making an exact copy of another animal and plant.problemstwo majoreffectSummary:The passage mainly talks about cloning.Cloning has not only advantages but also causes arguments.People are concerning the future of cloning