人教版高中英语选修8 Unit2 Warming up 优质课件

1、CloningCloning Unit 2Unit 2differvi. 不同不同; 相异相异ObjectiveTo learn some basic information about cloning. A clone is an animal or plant produced naturally or artificially from the cells of another animal or plant and is exactly the same as it.Cloning is a way of making an exactcopy of another animal or

2、 plant. The clone has the same DNA as the parent. Whats cloning?Whats cloning?Sounds Reasonable? There are different types of cloning, and cloning technologies can be used for other purposes besides producing the genetic twin of another organism. The three types of cloning technologies are: (1) reco

3、mbinant DNA technology or DNA cloning（基因重组克隆技术）（基因重组克隆技术） (2) reproductive cloning（生殖性克隆）（生殖性克隆） (3) therapeutic cloning （治疗性克隆）（治疗性克隆）克隆克隆一词是英文单词一词是英文单词clone的音译，作的音译，作为名词，为名词，clone通常被意译为无性繁殖通常被意译为无性繁殖系。同一克隆的所有成员的遗传构成系。同一克隆的所有成员的遗传构成是完全相同的，例外仅见于有突变发是完全相同的，例外仅见于有突变发生时。自然界早已存在天然植物、动生时。自然界早已存在天然植物、动物和微

4、生物的克隆。物和微生物的克隆。 人们开始探索用人工的方法来生产高人们开始探索用人工的方法来生产高等动物克隆。这样，克隆一词就开始被用等动物克隆。这样，克隆一词就开始被用作动词，指人工培育克隆动物这一动作。作动词，指人工培育克隆动物这一动作。 目前，生产哺乳动物克隆的方法主要目前，生产哺乳动物克隆的方法主要有有胚胎分割胚胎分割和和细胞核移植细胞核移植两种。克隆羊两种。克隆羊“多莉多莉”，以及其后各国科学家培育的各，以及其后各国科学家培育的各种种克隆动物，采用的都是细胞核移植技术。克隆动物，采用的都是细胞核移植技术。 所谓细胞核移植所谓细胞核移植，是指将不同发育时期，是指将不同发育时期的胚胎或成体

5、动物的细胞核，经显微手的胚胎或成体动物的细胞核，经显微手术和细胞融合方法移植到去核卵母细胞术和细胞融合方法移植到去核卵母细胞中，重新组成胚胎并使之发育成熟的过中，重新组成胚胎并使之发育成熟的过程。由于细胞核移植是产生克隆动物的程。由于细胞核移植是产生克隆动物的有效方法，故人们往往把它称为有效方法，故人们往往把它称为动物克动物克隆技术隆技术。 In pairs, look at these pictures and discuss which ones are natural clones and which ones are man-made. Think about how they dif

6、fer.QuizQuizDolly the sheepA strawberry plantNatural cloneMan-made clone一株草莓依靠它沿地一株草莓依靠它沿地“爬走爬走”的匍匐的匍匐茎茎, 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。Growing new plantsTwinsNatural cloneMan-made cloneNatural clone is one that occurs in nature without human help. Man-made clone is one that is produced through human

7、intervention (介入介入).CloneCan you tell the difference between natural clone and man-made clone?Cactus (仙人掌仙人掌)Pendulum orchid(吊兰吊兰)natural clone examplesnatural clone examplesman-made clone examples man-made clone examples Im celebrity in the history of cloning. Do you know my name? Dolly, the first

8、mammal to be cloned from adult DNA, was put down by lethal injection on Feb. 14, 2003. Prior to her death, Dolly had been suffering from lung cancer and crippling arthritis (严重的严重的关节炎关节炎). Celebrity Sheep DollyCelebrity Sheep DollyDolly是世界上第一是世界上第一例用体细胞例用体细胞乳乳腺上皮细胞，通过腺上皮细胞，通过细胞核移植技术，细胞核移植技术，在复杂的人工操作

9、在复杂的人工操作下，得到的一只小下，得到的一只小绵羊。绵羊。Scientists have been cloning animals for many years. The creation of Dolly isthe first mammal cloned from the cell of an adult animal. Since Dolly, researchers have cloned a number of large and small animals including sheep, goats, oxen, mice, pigs, cats, rabbits and so

10、 on. All these clones were created using nuclear transfer technology (细胞核移植技术细胞核移植技术). What animals have been cloned? What animals have been cloned? The mule in the picture is the worlds first cloned mule. It was born on 4 May 2003. His name is Idaho Gem. The kitten in the picture is called Cc. Its

11、name is from “Copycat”. It was born in December 2002. These female pigs are also cloned. They are born on Christmas Day 2001. They are Noel, Angel, Star, Joy and Mary.The pair of calves were born on 5 July 1998 in Ishikawa, Japan. They were two years younger than Dolly, being second adult animal clo

12、nes in the world.If possible, do you want another person to be exactly the same as you? Why or why not? DiscussionDiscussionImportant Important events in events in cloning historycloning historyIn 5000 B.C. (谷物选种谷物选种) Human beings began to choose the best seeds from some kinds of crops. That was the

13、 beginning of controlling life according to humans will. In 1978: The first case of tube infant (试管婴儿试管婴儿) appeared.A British doctor used the sperm (精子精子) of a man and fertilized (使使受精受精) it in a test tube (试管试管) and then transplanted (移植移植) the embryo (胚胎胚胎) into the womb (子宫子宫) of a healthy mother

14、.The first tube infant called Louis appeared.In 1996: The famous sheep “Dolly” was cloned successfully.Dolly is together with her mother. In 1998: A series of things were cloned.vThe scientists in Hawaii University cloned over 50 mice.vSome private institutions (协会协会) successfully cloned little oxen

15、.Nowadays: Cloned dogs, mice, rabbits, goats, oxen, pigs appeared. China became the seventh country thathas the ability to clone pigs. China has succeededin using embryonic (胚胚胎的胎的) cells to clone many animals.1 Clone can be from both natural clone and man-made clone. 2 The sheep, named Kitty was th

16、e first successful clone of a mammal. 3 Only strawberries and cactuses (仙人掌仙人掌) are natural clones.4 Since Dolly, researchers have cloned a number of large and small animals including cats, rabbits and horses.5 A parent can clone a child who is dying of a terminal illness (不治之症不治之症). T or T or F FAc

17、cording to what weve learned, in pairs discuss what you understand about cloning. Then list the questions you want to find out. Share your lists with one another.Questions about cloningQuestions about cloning1. How is a clone produced?2. What benefits can humans gain from cloning?3. What problems ma

18、y arise when humans are cloned?1. 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 19

19、96.2. What benefits can humans gain from cloning?1) Medical cloning can help cure serious illnesses that ruin ones quality of life (such as Parkinsons disease 帕金森氏帕金森氏症症 or Alzheimers disease 阿尔茨海默阿尔茨海默氏症氏症).2) It can help infertile people have babies.3. What problems may arise when humans are cloned?1) Peo