The researchers, led by Hwang Woo-suk, insist they cloned an Afghan hound, only

The researchers, led by HwangWoo-suk, insist they cloned an Afghan hound, only to help investigate (研究) human disease, including thepossibility of cloning stem cells (干细胞) for treatment purposes.

But others immediately renewedcalls for a global ban on human reproductive cloning before the technologymoves any farther.

“Successful cloning of an increasing number of species confirmsthe general impression that it would be possible to clone any species of mammals,including humans,” said Ian Wilmut, a reproductivebiologist at the University of Edinburgh who produced the first cloned mammal,Dolly the sheep, from an adult cell nearly a decade ago.

Researchers have since clonedcats, goats, cows, mice, pigs, rabbits, horses, deer, mules and gaur, a largewild ox of Southeast Asia. So far, efforts to clone a monkey or another primatewith the same techniques have failed.

Uncertainties about the health andlife span (寿命)of cloned animals continue to exsist; Dolly died at a young age in 2003 afterdeveloping cancer and arthritis.

Wilmut and others complimentedHwang’s achievement, reported Wednesday in thejournal Nature. But they said politicians and scientists must face the largerissue — how to go on with the research withoutcrossing the moral boundary of copying human life in the lab.

“The ability to use the technology is hopeful,” said Robert Schenken, president of the American Society forReproductive Medicine. “However, the paper also pointsout that in dogs as in most species, cloning for reproductive purposes isunsafe.”

The cloned puppy was the lonesuccess from more than 100 dogs implanted (嵌入)with more than 1,000 clonedembryos.

In a news conference in Seoul,the cloning team also condemned the reproductive cloning of humans as “unsafe and inefficient.”Human reproductive cloning already is banned in South Korea. Other nations,including the United States, are divided on whether to ban just human cloningor cloning of all kinds, including the production of stem cells.

1. An Afghan hound is a kind of ______.

   A. cat               B.dog          C. cow          D.goat

2. A ______ is a large wild ox of SoutheastAsia.

   A. horse         B.deer        C. mules            D.gaur

3.Accrding to the passage, scientists haven’t been able to clone a ______ so far.

   A.deer           B.mule            C.monkey       D. mouse

4.The underlined word complimented is probablysimilar in meaning to ______.

   A.praised      B. doubted         C. refused      D. gave up

5.The cloning of human beings is banned in______. 

   A. South Korea                     

B. the United States

C. both South Korea and theUnited States  

D.neither South Korea nor the United States

试题答案

【答案】

1.B

2.D

3.C

4.A

5.A

【解析】 略