选修8Unit2reading课件

1、Look at the following pictures.Which is natural clone? Which is man-made clone?What can you see in the picture?We can see a strawberry plant producing runners (匍匐茎匍匐茎)in a natural form of cloning.Who cut the stem off the plant?A gardener. The gardener is going to put it into a pot to produce another

2、 plant. Cactus (仙人掌仙人掌)orchid(兰花兰花)natural clone examplesnatural clone examplesThey are identical in sex and appearance, who are produced from the same original egg. TwinsNatural clones2001 cloning cattle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克胚胎细胞克隆兔。隆兔。2002 cloning

3、 cats第一只克隆宠物猫第一只克隆宠物猫克隆马及其克隆马及其“母母亲兼姐姐亲兼姐姐”2005 cloning dogs克隆的荧光小猪克隆的荧光小猪(左左)和正常小猪和正常小猪(右右)Cloning is a way of making an exact copy of another animal or plant. It includes natural cloning and man-made cloning.Whats cloning?Whats cloning?Natural clone is one that occurs in nature without human help.

4、 Man-made clone is one that is produced through human intervention (介入介入).CloneCan you tell the difference between natural clone and man-made clone?Dolly the sheepShe was cloned while the others were born naturally.How does Dolly differ from other sheep?Dolly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

5、胞核移植技术，细胞核移植技术，在复杂的人工操作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。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 _. controversialprocedureRead the text quickly and complete its main idea._.Cloning has two major uses _.What is cloning?

6、_. The effect of Dolly._. It is forbidden to clone human beings._.The problems of Dolly.123452. Give the right order of the main idea of each paragraph.True or false :1.Electricity is needed in the procedure.2.Sheep B provides a somatic cell for the clone.3.The lamb is the exact copy of sheep A.TTFS

7、tep 3. Careful-reading4. Cloning means making a copy of an animal. 5. Cloning animals is as complicated as cloning plants. 6. Dolly the sheep was the first successful clone of a mammal. FFTChoose the best answers.1.The cloning of Dolly the sheep succeeded because_. A. its easier to clone a sheep tha

8、n 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 failed.The determination and patience of the scientists was rewarded/ paid off. 2. The lamb is the clone of the cell from sheepB

9、 because_. A. it provides the egg cell B. it gives birth to the lamb C. it provides the nucleus D. it is a female sheep3. In the second paragraph, the word “straightforward” means _.A. uncomplicated B. honest C. frank D. difficult猜词：猜词：4. Generally, an original sheep lives _ years old. A. 9 B. 10 C.

10、 13 D. 6.5C5. 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 oneC6. What about the writers attitude toward cl

11、oning in this passage?A.The writer is against cloning.B. The writer is in favor of cloning.C. The writer does not state any personal opinion about cloning.D. The writer is in agreement with cloning.DefinitionIt is a way of _ of another animal and plant.two major uses of cloning1)to produce _quantiti

12、es ofplants. 2)It is valuable for research on new _and medical research on _. making an exact copycommercialplant speciesanimalsAccording to the text, fill in the blanks.Cloning procedureCloning plants is _while cloning animals is very _.The first successful animal cloneThe cloning of_ is a _ in clo

13、ning technology.straightforwardbreakthroughDolly the sheepcomplicatedThe problems of Dolly the sheep Encouraging news : It seemed to develop _. Disturbing news:It lived for _ and a half years, half the length of the life of the _ sheep. normally6originalThe effect of Dolly the sheepIts appearance ra

14、ised a storm of _ and had a great impact on the _ and public_. It opened everybodys eyes to the possibility of using cloning to cure _and even to produce _.objectionshuman beingsimaginationserious illnessesmediaArguments on cloningEvil leaders hope to clone _. Religious leaders raised _ questions.Ma

15、ny governments _ research into human cloning. Some countries continued to _evidence of the abundant medical aid.moralforbadethemselvesaccumulateIs cloning beneficial or harmful to us ?Advantages Disadvantages Group 1 Group 2DebateAdvantagesMedical cloning could produce cures for serious illness in h

16、umans.Cloning plants can produce plants of similar quality for sale.Cloning plants can be useful for research on new plant species.Cloning can help save endangered animals.ProblemsAnimal clones may develop the illness of older animals.Animal clones may die younger than the original animals.Evil leaders may want to clone themselves.There are moral objections to cloning human beings.1.We can conclude _A. cloning is good for us.B. cloning has advantages and d