T: Reproductive cloning is a technology used to generate an animal that has the same nuclear DNA as another currently or previously existing animal. Dolly was created by reproductive cloning technology. She was the first mammal to be cloned from adult DNA taken from an adult cell. Previously, animals had only been cloned using embryo cells which already have the potential to become a complete embryo in its own right. The big breakthrough with Dolly was to make a clone from an ordinary, adult cell − in this case from a female goat's udder.

S: Have you seen Jurassic Park? In this feature film, scientists use DNA preserved for tens of millions of years to clone dinosaurs. They find trouble, however, when they realize that the cloned creatures are smarter and fiercer than expected. Could we really clone dinosaurs?

T: In theory? Yes. What would you need to do this? A well-preserved source of DNA from the extinct dinosaur could serve as a surrogate mother. In reality? Probably not. It's not likely that dinosaur DNA could survive undamaged for such a long time. However, scientists have tried to clone species that became extinct more recently, using DNA from well-preserved tissue samples.

More questions about cloning are given in the appendix. The information above is for reference only. Or you can choose several students and ask them to act out a short play whose main topic is as follows:

An old man who was dying left all his fortune to his own son. But he did not know that his son was cloned. So two same young men both claimed that they were the old man's son. They quarreled and fought with each other; at last they went to the judge. The judge let them check DNA. The result was that their DNA was the same. Now even the judge did not know what to do.

In this part the teacher can give the students some advice to act out. According to this play teacher ask the students several questions:

1. Do you want to be cloned or not? Why?

2. If you are the judge what will you do?

3. Can you tell me the advantages of cloning?

4. And what is the disadvantage?

Discussion

In this part the students will discuss the relationship between the development of technology and