2016-2017学年高中英语 Module 5 Cloning课件 外研版选修6.ppt

Cloning 克隆技术自诞生以来一直存在着很大的争议，你想了解此技术的起源、发展和现状吗？快到文章中去寻找答案吧！ Saving lives has always been an important mission of science research.Now science research，indeed all society，is facing a new dilemma：whether or not to try and save more lives through human cloning. The first cloning experiments in the 1950s involved frogs and toads.It was not until 1997 that scientists successfully cloned the first mammal，the world-famous sheep—Dolly.Cloning techniques have continued to improve since then，and today there are cloned mice，salmon，and cattle. Some scientists want to apply the methods used in cloning animals to produce skin，organs，and other body parts for humans.One of these methods involves taking adult cells from the brain or blood and growing them into new tissues.Another，more complex，technique takes embryo cells and develops them into a wide variety of cell types and tissues.It is this planned use of human embryos that has resulted in serious argument and criticism. The cloning of human cells provides the potential to find cures and eliminate diseases.The dream of some researchers is to create a utopian (乌托邦) world of good health.Others question whether it is right to “Play God” in an attempt to cure the disabilities and diseases of this world. Some of the great hopes for cloning include the ability to perform transplants，whenever they are needed，using cloned organs.For example，people with lung cancer may simply have their lungs replaced with healthy ones.Scientists also look forward to the day when people in wheel chairs can walk again，and illnesses such as Alzheimer’s and Parkinson’s Disease can be prevented. Many people fear the effects cloning could have on our society.They imagine masses of identical people，and the production of “perfect” humans for warfare or slave labor.We might see headless human bodies being stored at hospitals for their “spare parts”．With such thought-provoking possibilities for the 21st century，human cloning will no doubt continue