新视野大学英语视听说教程第四册答案Unit8..doc

Uint8 II. Basic Listening Practice Script M: Scentists claim the world population has 99.5% of the same DNA. W: But this doesn’t tell us there is no such thing as race. Q: What is true of the DNA of difference races? Script W: With the advent of the genetic map we know where everything is, but do we know where to go with it? M: Your map seems to differ largely from my geographical map! Q: What does the man imply? Script M: As you know, it has taken millions of years of evolution and natural selection to get us where we are today. W: Yes, but now that we have genetic engineering, we seem to have decided that we want to be God. Q: What does the woman imply? Script M: I think the research into cloning will lead us into dangers, filling us with false hopes of perfection. W: It’s too late to turn back the clock. We’ll just have to depend on common sense to solve uncommon problems. Q: What does the woman mean? Script W: In America, many prisoners are having their cases reviewed, and some have even been freed through DNA testing. M: Except for the ones whose death sentence has already been carried out. Q: What can we learn about DNA testing from the dialog? Keys: 1.B 2.C 3.D 4.A 5.C III. Listening In Task 1: Stem Cell Research Script Gregory: The Republican party in America is opposing stem cell research. I find it hard to believe that in this day and age, someone would do that. Lillian: Stem cell research sounds pretty impressive, I’ll admit. But just what is it? Gregory: Well, a stem cell is a special type of cell. It is a general cell that, when it devides, can become any specific type of cell. Lillian: You mean, a stem cell can become a heart cell? Or a brain or a kidney cell? Gregory: That’s about it. Stem cells are a part of the body’s maintenance and repair system. When they divide, they can become any cell type. Lillian: I guess there would be some tremendous m