中小学教育资源及组卷应用平台 【北师大版】Unit 9 Human Biology 类文赏读 话题导入 Cloning：Where Is It Leading Us Cloning has always been with us and is here to stay.It is a way of making an exact copy of another animal or plant.It happens in plants when gardeners take cuttings from growing plants to make new ones.It also happens in animals when twins identical1 in sex and appearance are produced from the same original egg.The fact is that these are both examples of natural clones. Cloning has two major uses.Firstly，gardeners use it all the time to produce commercial2 quantities of plants.Secondly，it is valuable for research on new plant species and for medical research on animals.Cloning plants is straightforward3 while cloning animals is very complicated4.It is a difficult task to undertake5.Many attempts to clone mammals failed.But at last the determination and patience of the scientists paid off in 1996 with a breakthrough6—the cloning of Dolly the sheep.The procedure7 works like this： ... On the one hand，the whole scientific world followed the progress of the first successful clone，Dolly the sheep.The fact that she seemed to develop normally was very encouraging.Then came the disturbing news that Dolly had become seriously ill.Cloning scientists were cast down to find that Dolly’s illnesses were more appropriate to a much older animal.Altogether Dolly lived six and a half years，half the length of the life of the original sheep.Sadly the same arbitrary fate affected other species，such as cloned mice.The questions that concerned all scientists were：“Would this be a major difficulty for all cloned animals？Would it happen forever？Could it be solved if corrections were made in their research procedure？” On the other hand，Dolly’s appearance raised a storm of objections and had a great impact on the media8 and public imagination.It became controversial.It suddenly opened everybody’s eyes to the possibility of using cloning to cure serious illnesses and even to produce human beings. 1．identical/a 'dent kl/ adj.同一的；一模一样的 2．commercial/k 'm l/ adj.商业的；贸易的 3．straightforward/ stre t'f w d/ adj.简单的；直接的；坦率的 4．complicated/'k mpl ke t d/ adj.复杂的；难懂的 5．undertake/ nd 'te k/ v．(undertook；undertaken)着手；从事，承担 6．breakthrough/'bre kθru / n．突破 7．procedure/pr 'si d / n．程序；步骤；手续 8．the media大众传播媒体(如电视、报纸等) INCLUDEPICTURE "E:\\马珊珊\\2021\\同步\\第三批\\英语 北师大 选择性必修第三册\\靓句背诵.TIF" \* MERGEFORMAT INCLUDEPICTURE "E:\\马珊珊\\2021\\同步\\第三批\\英语 北师大 选择性必修第三册\\靓句背诵.TIF" \* MERGEFORMATINET INCLUDEPICTURE "E:\\马珊珊\\2021\\同步\\第三批\\英语 北师大 选择性必修第三册\\word\\靓句背诵.TIF" \* MERGEFORMATINET INCLUDEPICTURE "E:\\马珊珊\\2021\\同步\\第三批\\英语 北师大 选择性必修第三册\\word\\UNIT 9 HUMAN BIOLOGY\\靓句背诵.TIF" \* MERGEFORMATINET INCLUDEPICTURE "C:\\Users\\14902\\Desktop\\高中英语讲义北师大版\\高中英语讲义北师大版\\高中英语讲义北师大 ... ...
