大学英语综合教程3Unit-8答案

大学英语综合教程 3Unit-8 答案Unit 8

Part I Pre-Reading Task

Script for the recording:

A Clone of Our Own

Will humans be the next clones? The technology still has a long way to go before it's considered safe to try on humans. But even if it were safe, would it be right? Let's hear what Professor Hank Greely of Stanford University has to say on this topic .

Interviewer: When will we clone a human?

Greely: That's not a simple question. I think we have to ask ourselves: is there something about the technology that is so wrong or so evil that it shouldn't be used at all? Or should it be judged according to its intended uses? Interviewer: What are acceptable uses?

Greely: We really need to distinguish between different types of cloning. If we use cloning to grow a new liver, I don't think many people will have problems with that - as long as it's growing a liver and not taking a liver from a cloned person. Human reproductive cloning is

much trickier. Interviewer: Why?

Greely: Safety. There's still a very low success rate. With Dolly, the first cloned lamb, 29 treated eggs were implanted in sheep to get one Dolly. We don't worry too much about sheep miscarriages or about deformed lambs being born. But we would with humans. And we wouldn't know if a human clone would be healthy. Interviewer: Dolly appears to be healthy. Why wouldn't a human clone be so?

Greely: There may be cell changes that are initially invisible and only show themselves as the clone ages. There's also a problem with the ends of chromosomes in cells,

which shorten until the cells can no longer reproduce. We know that Dolly's

chromosomes are shorter than those of other sheep her age, and we don't know

what that means yet.

- 188 - Appendix I

Interviewer: Suppose human cloning was safe. In what situations do you see cloning being used?

Greely: Helping parents who are having difficulty having children would be one area. Interviewer: Are there other situations where it might be acceptable to create a human clone? Greely: A situation where parents want to create a new child to be a bone marrow donor for an older sick child. That's a real tough one. But that issue might never arise if we succeed in growing bone marrow outside the body. Another situation is cloning a child who has accidentally died. I think that's disturbing. But I've never been in that position and so I don't feel comfortable saying whether that's a good application or a bad application of the technology. Interviewer: What about cloning a Hitler or Michael Jordan ?

Greely: I think we can dismiss those as bad or even silly applications. Interviewer: Is there anything else you'd like to say about the future of human cloning?

Greely: Even if cloning humans were safe and we as a society had decided it was right and proper for reproductive purposes, I don't think we'd see a lot of clones. The oldfash-ioned way of making

babies has a lot going for it: It's easy, traditional, well understood, and occasionally even pleasant.

People are not going to give up sex anytime soon.

Part II Text A

Texf Organization

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