The researchers, led by Hwang Woo-suk, insist they cloned an Afghan hound, only to help investigate (研究) human disease, including the possibility of cloning stem cells (干細胞) for treatment purposes.

But others immediately renewed calls for a global ban on human reproductive cloning before the technology moves any farther.

“Successful cloning of an increasing number of species confirms the general impression that it would be possible to clone any species of mammals, including humans,” said Ian Wilmut, a reproductive biologist 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 cloned cats, goats, cows, mice, pigs, rabbits, horses, deer, mules and gaur, a large wild ox of Southeast Asia. So far, efforts to clone a monkey or another primate with the same techniques have failed.

Uncertainties about the health and life span (壽命) of cloned animals continue to exsist; Dolly died at a young age in 2003 after developing cancer and arthritis.

Wilmut and others complimented Hwang’s achievement, reported Wednesday in the journal Nature. But they said politicians and scientists must face the larger issue — how to go on with the research without crossing 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 for Reproductive Medicine. “However, the paper also points out that in dogs as in most species, cloning for reproductive purposes is unsafe.”

The cloned puppy was the lone success from more than 100 dogs implanted (嵌入)with more than 1,000 cloned embryos.

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 cloning or cloning of all kinds, including the production of stem cells.

43． An Afghan hound is a kind of ______.

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

44． A ______ is a large wild ox of Southeast Asia.

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

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

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

46．The underlined word complimented is probably similar in meaning to ______.

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

47．The cloning of human beings is banned in ______.

　 A. South Korea　　　　　 　　　　　　　　

B. the United States

C. both South Korea and the United States　

D. neither South Korea nor the United States

43．B

44．D

45．C

46．A

47．A

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科目：高中英語 來源：皇冠優(yōu)化名題　高中英語 題型：050

　　Sweet potatoes are fat-free,high in fiber and full of the vitamins that research suggests reduce your risk of life-shortening diseases．To stay healthy,we must eat more fruits and vegetables,and sweet potatoes are a great source of beta carotene（胡蘿卜素）and other carotenoids．According to a study of the diets of almost 90,000 nurses,eating about one cup a day of fruils and vegetables rich in carotenoids(which the body turns into vitamin A)can cut your risk of stroke in halt and reduce your risk of heart disease by 22 percent．Other resear chsuggests beta carotene protects against breast,lung and stomach cancers．

　　Beta carotene is the most famous member of the carotenoids family．In fact,a medium sized sweet potato contains nearly 12 mg of beta carotene(antiaging experts usually suggest 6 to 11 mg perday)．Sweet potatoes are also a low-fat source of vitamin E．Research has linked high E diets with a lower risk of heart disease．This vitamin pill in an orange jacket also packs a vitamin C punch-it has more C than apricots(a kind of fruit)．Research suggests that vitamin C protects against ailments ranging from cataracts(an eye disease)to cancer．In addition,A UCLA(University of California,Los Angels)study linked high vitamin C diets with a longer life．Recent studies have showed that antioxidant vitamins C,E and beta carotene fight a fierce battle against free radicals（自由基）,which cause cell（細胞）damage and lead to various illnesses．Therefore,to keep fit,eat more sweet potatoes．

(1)

According to the text,there exists a lot of ________ in sweet potatoes．

[　　]

A．

fiber,beta carotene,other earotenoids,vitamin E and C

B．

beta carotene,other carotenoids,fiber,vitamin A and E

C．

vitamin A,beta carotene,fiber,vitamin E and C

D．

beta carotent,other carotenoids,vitamin A and E

(2)

This text as a whole suggests that eating sweet potatoes can help ________

[　　]

A．

cut your risk of stroke and heart disease

B．

protect against breast,lung and stomach cancers

C．

protect against ailments ranging from cataracts to cancer

D．

you stay healthy and reduce your risk of life shortening diseases

(3)

“This vitamin pill in an orange jacket”in the passage refers to ________

[　　]

A．

sweet potato

B．

vitamin C pill

C．

vitamin E pill

D．

beta carotene

(4)

The best title of this passage might be ________

[　　]

A．

The Vitamin Superstar

B．

On Sweet Potatoes

C．

Beta Carotene and Vitamins

D．

Diet and Disease

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科目：高中英語 來源： 題型：053

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閱讀下面短文，從所給四個選項中，選出最佳答案。

　Can trees talk? Yes——but not in words． Scientists have reason to believe that trees do communicate (互通信息) with each other． Not long ago, resear- chers learned some surprising things． First a willow tree(柳樹)attacked in the woods by caterpillars(毛毛蟲)changed the chemistry of its leaves and made them taste so terrible that the caterpillars got tired of the leaves and stopped eating them． Then even more astonishing, the tree sent out a special vapour — a signal causing its neighbours to change the chemistry of their own leaves and make them less tasty．

　　　Communication, of course, doesn't need to be always in words． We can talk to each other by smiling, raising our shoulders and moving our hands． We know that birds and animals use a whole vocabulary of songs, sounds, and movements． Bees dance their signals, flying in certain patterns that tell other bees where to find nectar(花蜜)for honey． So why shouldn't trees have ways of sending messages?

1． When attacked, a willow tree will protect itself by________．

[　　]

A． changing its leaves’chemistry

B． changing its leaves’colour

C． talking to caterpillars

D． sending a special vapour

2． From the passage we know that catrpillars________．

[　　]

A． like willow trees

B． enjoy eating fallen leaves

C． feed on willow tree leaves

D． could communicate with willow trees

3． Caterpillars will stop eating willow tree leaves which________．

[　　]

A． have a chemical change and become tasteless

B． have a pleasant taste

C． are being attacked

D． are communicating

4． According to the passage, how do willow trees communicate with each other?

[　　]

A． They talk in words．

B． They send out a special vapour．

C． They wave their leaves．

D． They make special sounds．

5． According to the passage, bees communicate with each other by______．

[　　]

A． talking

B． making unusual sounds

C． singing songs

D． fly in certain patterns

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