日日人人_亚洲美女在线视频_av手机在线播放_国产大片aaa_欧美中文日韩_午夜理伦三级

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(xì)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 condemnedthe 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.
【小題1】 An Afghan hound is a kind of ______.

A.catB.dogC.cowD.goat
【小題2】 A ______ is a large wild ox of Southeast Asia.
A.horseB.deerC.mules D.gaur
【小題3】Accrding to the passage, scientists haven’t been able to clone a ______ so far.
A.deerB.muleC.monkeyD.mouse
【小題4】The underlined word complimented is probably similar in meaning to ______.
A.praisedB.doubtedC.refusedD.gave up
【小題5】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


【小題1】B
【小題1】D
【小題1】C
【小題1】A
【小題1】A

解析

練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

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(xì)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

查看答案和解析>>

科目:高中英語 來源: 題型:053

閱讀理解:   

閱讀下面短文,從所給四個(gè)選項(xiàng)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 leaveschemistry

B changing its leavescolour

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

查看答案和解析>>

同步練習(xí)冊(cè)答案
主站蜘蛛池模板: 久久综合九九 | 午夜国产一级 | 欧美一区久久 | 成年无码av片在线 | 成年入口无限观看网站 | 免费超碰在线 | 亚洲精品视频导航 | 国产精品一区二区免费在线观看 | 污网站观看| 欧美一级爆毛片 | 日日干夜夜操 | 奇米色777欧美一区二区 | 亚洲日本韩国欧美 | 黄av在线| 久久精品亚洲 | 99精品国产在热久久 | 这里只有精品在线视频观看 | 久久中文字幕视频 | 亚洲美女网址 | 黄色毛片视频网站 | 久久伊人在 | 一级做a爰片性色毛片 | 午夜精品成人一区二区 | 在线观看xxx | 久草网站 | 欧美亚洲视频 | 国产精品久久久久影院 | 精品亚洲一区二区三区 | 国产一区免费视频 | 一区二区三区欧美在线 | 青青草国产 | 成人欧美一区二区三区黑人孕妇 | 久久99欧美 | 欧美日韩国产在线观看 | 免费av电影网站 | 青青草综合在线 | 亚洲精品www| 日本精品区 | 成人影 | 亚洲第一成年免费网站 | 激情五月婷婷综合 |