新視野大學(xué)英語(yǔ)視聽(tīng)說(shuō)教程第四冊(cè) Unit 8 Task3: The First Cloned Cat

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In the age-old battle of cats and dogs, score one for the cats. Researchers at Texas A&M University recently announced that they have successfully cloned a cat name Rainbow—the first pet ever cloned—after several years of unsuccessful efforts to clone a dog name Missy.

The ork, financed by a company hoping to provide pet-cloning services to wealthy owners, adds cats to a growing list of successfully cloned animals that includes pigs, sheep, cattle and mice.

The success demonstrates cloning is a technology that could be transferred to other animal families as well. The accomplishment may provide new tools for studying diseases such as cats’ AIDS, a valuable research model for AIDS in humans.

Research into animal cloning remains an important scientific alternative until the issue of human cloning is settled. And that seems unlikly in the immediate future, for it involves religious and moral principles. There are, for example, groups that insist no one should be allowed to take on the role of God the Creator.

To create cloned cat embryos for the experiment, researchers transferred DNA from adult cat cells into egg cells stripped of their own genetic information. Out of 82 attempts with cloned embryos, one attempt resulted in a failed pregnancy, and another yielded a kitten named CC, delivered from a surrogate mother on December 22. The kitten’s name refers to “Carbon Copy” and “Copycat”, the name of the cloning project.

Cloning attempts with dogs have proven unsuccessful in part because dogs’reproductive cycles are more complicated.

The technique may also work with endangered cats such as the African wildcat, fishing cat and blackfooted cat.

Ironically, the increased knowledge of cat reproduction may best be suited for developing cat contraceptives to control the U.S. cat population.

1.Which of the following would be the best title for the passage?

1. What did researchers at Texas A&M University recently announce?

2. Which animals are NOT mentioned in the passage as having been cloned?

3. According to the passage, why is human cloning unlikely to happen in the near future?

4. What does the passage say about the pregnancy and birth in cat cloning?

Keys: 1.A 2.B 3.C 4.B 5.C