CloningWhereIsItLeadingUs課件.pptVIP

Discussion: 1.why do you think there is more controversy over animal cloning than over plant cloning? 2.Why do you think animal cloning is more difficult than plant cloning? 3.why do you think scientists persevere with animal cloning when it is so difficult? 4.what is the major problem for the animal clone? 1. The bell ______ the end of the period rang, _______ our heated discussion. A. indicating; interrupting B. indicated; interrupting 2.----My sons are not a little restless. ----Oh? Boys ____ be boys. A. should B. can C. may D. will * Cloning Where Is It Leading Us? Pre-reading Look at the pictures and discuss which ones are natural clones and which ones are man-made. Pictures 2 , 4 A natural clone is one that occurs in nature. Pictures 1, 3, 5 A man-made clone is one that is produced through human intervention.(干涉) Dolly the sheep Dolly is a man-made clone and her birth procedure is explained in the first reading. She is an exact copy of the sheep that provided her genetic information. Her lamb was produced as a natural birth. A strawberry plant This is a strawberry plant which produces runners(长匐茎，纤匐枝) in a natural form of cloning. The new plants are exact copies of the original plant. Growing new plants People cut the stem off the plant and put it into a pot to produce a new plant. Twins They are identical in sex and appearance and are good examples of natural clones. Twins carry the same genetic(遗传的) information. Identical dogs This is the first cloned dog in the world (August 3rd,2005) and was produced by a lab in South Korea. It is called Snuppy and is an Afghan hound (猎犬). T or F questions: Gardeners can make a lot of money by cloning plants. Cloning animals is as complicated as cloning plants. Dolly the sheep was the first successful clone of a mammal. Natural clones happen in animals as well as in plants. Main ideas: 1.What is cloning?/definition 2.Two major uses of clo