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2009年6月英语六级考试快速阅读实战练习(2)8900字 The world was stunned by the news in the summer of 1995, when a British embryologist named Ian Wilmut, and his research team, successfully cloned Dolly the sheep using the technique of nuclear transfer. Replacing the DNA of one sheeps egg with the DNA of another sheeps the team created Dolly. Plants and lower forms of animal life have been successfully cloned for many years, but before Wilmuts announcement, it had been thought by many to be unlikely that such a procedure could be performed on larger mammals and life forms. The world media was immediately filled with heated discussions about the ethical implications of cloning. 简历大全 /html/jianli/ Some of the most powerful people in the world have felt compelled to act against this threat. President Clinton swiftly imposed a ban on federal funding for human-cloning research. Bills were put in the works in both houses of Congress to outlaw human cloning because it was deemed as a fundamentally evil thing that must be stopped. But what, exactly, is bad about it? From an ethical point of view, it is difficult to see exactly what is wrong with cloning human beings. The people who are afraid of cloning tend to assume that someone would, for example, break into Napoleons Tomb, steal some DNA and make a bunch of emperors. In reality, infertile people who use donated sperm, eggs, or embryos would probably use cloning. Do the potential harms outweigh the benefits of cloning? From what we know now, they dont. Therefore, we should not rush placing a ban on a potentially useful method of helping infertile, genetically at-risk, homosexual, or single people to become parents. 开题报告 /html/lunwenzhidao/kaitibaogao/Do human beings have a right to reproduce? No one has the moral right to tell another person that they should not be able to have children, and I dont see why Bill Clinton has that right either. If humans have a right to reproduce, what right does society have to limit the means? Essentially all reproduction done these days is with medical help at delivery, and even before. Truly natural human reproduction would make pregnancy-related death the number one killer of adult women. 思想汇报 /sixianghuibao/Some forms of medical help are more invasive than others. With in-vitro fertilization, the sperm and egg are combined in a lab and surgically implanted in the womb. Less than two decades ago, a similar concern was raised over the ethical issues involving test-tube babies. Today, nearly 30,000 such babies have been born in the United States alone. This miracle has made many parents happy. So what principle says that one combination of genetic material in a flask is acceptable, but not another? 毕业Nature clones people all the time. Approximately one in 1000 births is an identical twin. However, despite how many or how few individual characteristics twins have in common, they are still different people. They have their own identities, their own thoughts, and their own rights. They enter different occupations, get different diseases, and have different experiences with marriage, alcohol, community leadership, etc. Twins have different personalities as would cloned individuals. Even if someone cloned several Napoleons, each would be different and even more unique than twins; the cloned child would be raised in a different setting. Therefore, cloning does not rob individuals of their personality. 简历大全 /html/jianli/Perhaps the strongest ethical argument against cloning is that it could lead to a new, unfamiliar type of family relationship. We have no idea what it would be like to grow up as the child of parents who seem to know you from the inside. Some psychological characteristics may be biologically, or genetically, based. The parent would know in advance what crises a cloned teenager could go through and how he or she will respond. Because the parents may understand what the child is going through, to greater degree than most parents, it may produce a good and loving relationship in the long run. On the other hand, most children want to have their own space. Simply because a family relationship is new and untried is no reason to automatically condemn it. In the past, many types of family relationships were considered harmful, but later showed to cause no harm to the children. Among these is joint custody after divorce, gay and lesbian parenting, and interracial adoption. As with adoption, in-vitro fertilization, and the use of donor sperm, how the child will react to the news about his or her arrival in this world will depend on how the parents feel about their mode of reproduction. Parents and children may adjust to cloning far more easily than we might think, just as it happened with in-vitro fertilization. 开题报告 /html/lunwenzhidao/kaitibaogao/One recurring image in anti-cloning propaganda is of some evil dictator raising an army of cloned warriors. But who is going to raise such an army. Clones start out life as babies. It is much easier to recruit young adults than to take care of babies for twenty years. Remember that cloning isnt the same as genetic engineering. No one can make another superman and his super powers might have a slim chance of being genetically determined, but nothing is certain. 论文代写
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