高中英語 Unit2 Cloning Period4課件1 新人教版選修8.ppt

1、Extensive reading,The return of the dinosaurs ?,克隆技術(shù)大事記,1938年:德國(guó)科學(xué)家首次提出克隆想法。 1952年:科學(xué)家開始用青蛙進(jìn)行克隆實(shí)驗(yàn)。 1970年:克隆青蛙實(shí)驗(yàn)取得突破,青蛙卵發(fā)育 成了蝌蚪, 但是在開始進(jìn)食以后死亡。,1981年:科學(xué)家進(jìn)行克隆鼠實(shí)驗(yàn),據(jù)稱用鼠 胚胎細(xì)胞培育出了正常的鼠。 1984年:第一只胚胎克隆羊誕生。 1997年2月24日:英國(guó)羅斯林研究所宣布克 隆羊培育成功?？茖W(xué)家用取自一只 6歲成年羊的乳腺細(xì)胞培育成功一 只克隆羊。,1998年2月23日:英國(guó)PPL醫(yī)療公司宣布,該公司克隆出一頭牛犢“杰弗遜先生”。 19

2、98年7月5日:日本科學(xué)家宣布,他們利用成年動(dòng)物體細(xì)胞克隆的兩頭牛犢誕生。,1998年7月22日:科學(xué)家采用一種新克隆技術(shù),用成年鼠的體細(xì)胞成功地培育出了第三代共50多只克隆鼠,這是人類第一次用克隆動(dòng)物克隆出克隆動(dòng)物。 1999年5月31日:美國(guó)夏威夷大學(xué)的科學(xué)家,利用成年體細(xì)胞克隆出第一只雄性老鼠。,1999年6月17日:以美藉華人科學(xué)家楊向中為首的研究小組利用一頭13歲高齡的母牛耳朵上取出的細(xì)胞克隆出小牛。 2000年1月3日:美國(guó)著名華人楊向中,用體外長(zhǎng)期培養(yǎng)后的公牛耳皮細(xì)胞成功克隆出6頭牛犢。,2000年1月:美國(guó)科學(xué)家宣布克隆猴成功,這只恒河猴被命名“泰特拉”。 2000年3月14日

3、:曾參與克隆小羊“多利”的英國(guó)PPL公司宣布,他們成功培育出5頭克隆豬。,Please enjoy some pictures about dinosaurs.,霸王龍tyrannosaurus,劍龍stegosaurs,角龍 ceratopsids,雷龍 brontosaurus,翼龍pterodactyl,Answer the following questions:,1. Why shouldnt you clone an extinct animal if there isnt enough diversity in the group? 2.Why is it wrong to cl

4、one an extinct animal if it would have to live in a zoo? 3.Why cant you clone the DNA of animals that have been extinct longer than 10,000 years?,Reading,1. Why shouldnt you clone an extinct animal if there isnt enough diversity in the group?,Keys:,There will not be enough genetic variation in the g

5、roup to be able to resist new illnesses.,2. Why is it wrong to clone an extinct animal if it would have to live in a zoo?,It is not a good idea to clone an animal that would have to live in a zoo because it is not a suitable habitat to develop and increase its numbers. The zoo is not a natural envir

6、onment for a wild animal.,3. Why cant you clone the DNA of animals that have been extinct longer than 10,000 years?,The DNA of animals more than 10,000 years old is not suitable for cloning, for it cant survive so long.,The writer of the text_ A. is excited by the possibility of cloning fierce and e

7、xtinct animals B. believes that extinct animals can be brought back to life by cloning C. thinks it impossible or unsuitable to clone extinct animals like dinosaurs D. dreams of dinosaurs returning to the earth,主旨大意,2. The film Jurassic Park is popular because _. A. people are interested in the subj

8、ect of cloning B. all the actors are dinosaurs C. it was directed by a scientist who clones dinosaurs D. it proves very interesting,細(xì)枝末節(jié),A,3. Which of the following is true? _ Mice were cloned in 1981. B. Dolly the sheep was the first cloned animal. C. The name of the cloned cow is “Bison” D. China

9、was successful in cloning mammals.,4. The reasons why a group of cloned animals all die of the same illness do NOT include_. A. they have the same arrangement of genes B. there isnt enough diversity in the group for it to overcome illnesses C. the illness is a new one D. their arrangement of genes c

10、an not resist that new disease,5. We can infer from the text that_ A. scientists are experimenting to clone dinosaurs B. dinosaurs will never return to the earth C. cloned animals will only live in the zoo D. the DNA of dinosaurs can only survive 10,000 year,推理判斷,True or false.,Scientists are still

11、experimenting with cloning mammals because they think it can make money. The animals that have disappeared from the earth, like dinosaurs, can be brought back to life through cloning. If we can clone any extinct animals, we should let them live in a zoo.,F,F,F,1. The popularity of the film Jurassic

12、Park, in which a scientist clones several different kinds of extinct dinosaurs, proves how interested ordinary people are in the subject.,長(zhǎng)句難句,電影侏羅紀(jì)公園的歡迎證實(shí)了普通人對(duì)這一話題是多么感興趣,在該電影中一位科學(xué)家克隆了幾種不同的恐龍。 in which引導(dǎo)定語從句, how引導(dǎo)賓語從句。,2. From time to time people suggest that the animals that have disappeared from

13、the earth, like dinosaurs, can possibly be brought back to life through cloning. 人們時(shí)常設(shè)想從地球上消失的動(dòng)物,例如恐 龍,有可能通過克隆技術(shù)使它們復(fù)活。,from time to time有時(shí), 間或, 偶爾, = occasionally, now and then。,3. It is useless to clone an animal if there is not enough diversity in the group for it to overcome illnesses. 該群中如果沒有足夠的

14、多樣性使它克服疾 病,克隆動(dòng)物就沒有用。,當(dāng)動(dòng)詞不定式、動(dòng)名詞或從句作主語時(shí), 通常把它們放在謂語之后, 而用it作句子的形式主語。,4. Diversity in a group means having animals with their genes arranged in different ways. 群中的多樣性指的是擁有 基因排列方式不同的動(dòng)物。 with their genes arranged in different ways 作定語, in different ways 以不同的方式。,5. .but others will survive and pass on the

15、 ability to resist that disease to their children. .其他的將存活下來并傳遞給其后代抵抗 這種病的能力。,resist 作及物動(dòng)詞主要有三個(gè)義項(xiàng): 抵抗, 對(duì)抗; 抵擋, 防止; (與cannot, could not連用) 無法抗拒, 無法抵擋。,base on/upon 以為基礎(chǔ), 依據(jù) 其結(jié)構(gòu)為: base sth. on/upon sth. is based on/upon,6. Based on what we know now, you can not clone animals that have been extinct lon

16、ger than 10000 years.據(jù)我們現(xiàn)在所知, 絕種一萬年以上的動(dòng)物不能克隆。,May the best animal win! Which extinct animals are worth restoring by means of cloning? Choose one and use the information to help you argue why this animal should be restored to the earth.,Discussion,Great Auk (1844),Auroch (1627),Dodo bird (1755),Quagg

17、a (1883),A sample dialogue (P16),S1: I think the dodo bird should be returned to the earth. It hasnt been extinct very long. So its DNA will still be good enough for cloning. S2: Yes and sailors in the past always described the dodo as being a very friendly animal. So it would make a good pet. It wa

18、snt too large either.,I cant see any other extinct animals becoming a pet, can you? S1: No, indeed. 1 know its a bird like the Great Auk but neither of them could fly. So if you kept either, it wouldnt escape from a park, a family or its home in the wild. You could also farm a dodo, unlike all the o

19、thers, and produce many of them as exotic pets.,S2: And what about its large nutritious eggs? Just one would feed a large family. So theres more than one reason for producing it in commercial numbers. S1: Did you know that its meat is very tasty too! Perhaps it could be farmed like ostriches and pro

20、vide a good source of protein.,S2: The only problem is that it needs hot climate to survive. But thats easy to provide with all its other advantages. I dont think any of the other animals stands a chance against the dodo. S1: So we both agree that the best extinct animal to be cloned is the dodo bird. S2: Yes.,3. A sample report(p.17),The dodo is the most suitable animal to be cloned for severa