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111Unit 3 Science versus naturePeriod one Welcome to this UnitTeaching Aims:Enable the students to know something about cloning, and give their own opinions about cloning.Help the students learn how to describe the advantages and disadvantages of human cloning with the target language.Teaching important and difficult points:Talk about cloning and human cloning.How to describe the advantages and disadvantages of human cloning.Teaching Procedures Step1. Lead-inIn the last unit, we learned something about the environment. Now our earth is faced with a lot of problems.Q1: what are the problems? (复习一下第二单元所学的知识，为下文做铺垫)Water pollution, air pollution, rubbish, deforestation, desertification, and sandstormQ2: Lets have a competition. Please think that what we should do to protect our environment.The more the better. One measure is worth 10 points. (通过竞赛的形式激发学生的兴趣。为了使在这一轮竞赛中失利的同学继续保持信心，这轮比赛的分数要累计到下一轮竞赛中。)From these measures, we know that protecting the environment is everyones earth, including plants, animals, human beings. But, some rare animals are dying out, such as rhinoceros, northeast tiger, white-flag dolphin and giant panda.Q3: what should we do to protect them?build nature reserve make laws to prohibit them from being hunted cloningIn recent years, science is developing so fast that it is beyond our imagination. Cloning is one of the more advanced technologies.（通过设计一系列的问题来导入到本单元的主题“克隆技术”）Step2 Describing pictures.Today, we are going to learn some information about cloning , now lets enjoy some pictures. Picture1 Q1: Are you familiar with these pictures?Q2: What do you know about Dolly? The worlds first cloned mammal.Q3: Who created it? Scottish scientists.Q4: When was it created? On 22nd February 1996Q5 :Is she still alive? No, she died in 2003 because of lung disease.（设计这些问题是为了引起学生的兴趣，把这些知识都设计成问题形式是为了下文的一个竞赛做铺垫，加深学生对这些知识的印象）Dolly was world famous because she was exactly the same as her mother, in appearance and in genes. Now lets look at the process of her birth. First, we need three female sheep and take a kind of cell from the first sheep, then take out the center of the cell. And then take another kind of cell from the second sheep, and also take out the center of the cell, and then put the center of the cell taken from the first sheep into this kind of cell. And put this new cell into the third sheep, and then the cloned sheep Dolly was born. Do you understand? （通过看一个Flash来描述克隆羊Dolly的克隆过程，使的学生更加了解克隆技术以及克隆过程，这样印象深刻，便于学生理解记忆）Picture 2Besides Dolly, there are a lot of animals cloned. For example, Q1: Whats this? Its a mule ,but it isnt a common mule, it is the worlds first cloned mule. Its name is Idaho Gem. It was born on 4 May 2003 in America. It has a brother, Taz, was a racing mule that has won many competitions.Q2: Do you know which one runs faster, the cloned mule or the normal one? Can you guess?（设计这个问题是让学生进一步了解克隆动物的知识）Some scientists are also curious about the result, so in the 20th session of Winnemucca mule competition which was held in America Nevada, they found that two cloned mules both are the first in the primary competition, but in the finals, they only achieve the third and seventh. Picture3 The cat is very beautiful and lovely, do you think so?Q1: Whats the name of this cat? CcQ2: where is its name from? Its name is from “copycat”Scientist in the USA created it with a cell taken from its mother Rainbow. It was born in December 2002.Picture4There are five little pigs. They are also the cloned animals. Their names are Noel, Angel, Star, Joy and Mary. They are all female. They were born on Christmas Day 2001. They are from Scotland.Picture 5The pair of calves were born on 5 July 1998 in Japan. They were two years younger than Dolly, being the second adult animal clones in the world.Picture6The name of the cloned monkey is ANDi. It is from “inserted DNA” spelt backwards. It is the first genetically modified monkey. The technology is different from that used for Dolly. （接下来的几幅图片，大多数以填空的形式给出，因为学生对这些克隆动物的知识不了解，又没有条件去上网查找资料，所以以填空的形式给出，更能便于学生抓住重点理解掌握）Step3 CompetitionLets have another competition to check how much you remember about the information we have learned just now. Also, a piece of information is 10 points. Which group got the highest marks will get a present.（通过两次竞赛，既使学生复习了上个单元所学的知识，又轻松愉快的掌握了本节课所学的内容）What Name Who/ where When Other informationsheepDollyScottish scientists1996The worlds first cloned mammalDied in2003 because of lung disease.muleIdaho GemAmericaMay 4 2003His brother, Taz, was a racing mule that has won many competitions.catCcUSADec.2002Its name is from “copycatpigsNoel, Angel, Star, Joy and MaryScotlandChristmas Day 2001They are all female.calfJapanJuly 5,1998They were two years younger than Dolly, being the second adult animal clones in the world.monkeyANDiUSAJan,2000It is from “inserted DNA” spelt backwards. It is the first genetically modified monkey.Step4 DiscussionQ1: What do you know about cloning?Cloning is a new technology, which produces from its own cells.Cloning is a kind of biotechnology, which aims to produce exact copies of a single gene or other segments of DNA.（这个问题对于学生来说，只能笼统的回答，因为对克隆技术只是大概的了解，所以相对较难，结合教材知识，学生只能答出以上内容）Q2: What other cloned animals do you know about?Since the time Dolly was born, over 500 mammals, e.g., cows cats, goats, mice, have been cloned successfully.Q3: Do you think it would be a good idea to clone humans some day? Why or why not?I dont think it is a good idea to clone humans even though we might have the ability to do so in the future. From the ethical point of view, I believe the disadvantages of producing cloned animals outweigh the advantages. If not handled properly, great confusion could arise. Furthermore, if the technology is misused or stolen by evil people, great damage will be done. What if they cloned legions of criminals or murderers? The world would be turned upside down.（这两个问题都是课外的知识，通过第二个问题，学生可以进一步了解一些其它克隆知识以及克隆动物，有利于扩展知识面；而第三个问题是主观发挥题，学生可以自由表达思想，既可以锻炼口语，有可以培养独立思考能力，然后给出我自己的观点作为参考。）Step5 Homework1.Preview the text on Page 422.Search the Internet for more information about cloning(课后作业可以让学生进一步去了解克隆方面的知识)111
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