A recent announcement by scientists that they have successfully cloned the first human embryo (胚胎) has caused much debate and has shocked many people around the world. On the one hand,some scientists point out that if you clone an embryo,you can produce val?uable tissues and organs that could be used to save human lives. On the other hand,many people,including some scientists,disagree and fear that if mankind interferes with nature in this way,they may be on their way to producing a reallife Frankenstein's monster.

 Cloning is producing an exact copy of a plant or an animal using its cells. The first mammal to be cloned successfully from an adult cell was the sheep Dolly. She was born in 1996 and died in early 2003,at a much younger age than normal. When she was born,many people were angry because they thought cloning would create more diseases in the animal world. However,in general the scientists were praised for their wonderful scientific breakthrough.

 The Scottish scientist who created Dolly,Ian Wilmut,is shocked that some sci?entists are now considering cloning human beings. Although he researches cloning,his intention has never been to create copies of humans. Instead,he thinks research efforts should concentrate on creating new tissues and organs that could eventually be used to cure diseases like cancer. However,some people consider that cloning hu?man embryos with the intention of destroying them shows no respect for human life.

  While cloning human embryos is illegal in many countries,some scientists are already pushing ahead with research so as to deliver a cloned human baby. Severino Antinori,an Italian doctor,is one of the leaders in this kind of research. He has de?clared that he wants to be the first to clone a human being.

  In China,scientists have focused their efforts on cloning animals* as well as stem cells to be used in medical research. China has succeeded in producing clones of cows and goats,and continues to research ways in which cloning can benefit mankind.

5. Which of the following statements about cloning is TRUE according to the passage?

   A. Cloning technology can only be applied to animals.

   B. A cloned animal can live longer than a normal one.

   C. People all over the world are happy about the birth of Dolly.

   D. Cloning can produce valuable tissues and organs to cure human diseases.

6. The reasons why people are anticloning include the following EXCEPT that      

   A. cloning may produce a reallife Frankenstein's monster

   B. cloning might create more diseases in the animal world

   C. cloning can't help those who want to clone their dead children

   D. cloning human embryos shows no respect for human life

7. Who is in favour of cloning human beings?

   A. Ian Wilmut. B. Severino Antinori.

   C. The author. D. The Chinese scientists.

8. What can be inferred from the last two paragraphs?

   A. If we interfere with nature,we will change the world to be what we want.

   B. It is impossible to clone babies for women who cannot have ones.

   C. Cloning human beings is illegal in many countries,so no scientists want to do so.

   D. Whether cloning human embryos is legal or not remains a matter of debate.

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 [2015 •辽宁沈阳东北育才中学一模]

 American researchers found females are the more talkative sex because of a special "language protein" in the brain.

 The study,conducted by neuroscientists (神经学家) and psy?chologist from the University of Maryland,concluded that women talked more because they had more of the FoxP2 protein. The research,published in The Journal of Neuroscience,found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previ?ously claimed that ladies speak about 20,000 words a day―over 13,000 more than men. "This study is one of the first to report a sex difference in the expression of a languageassociated protein in humans or animals," said Professor Margaret Mc?Carthy,who led the study. In their study,the researchers attempted to determine what might make male rats more vocal than their female friends.

 They separated four-day-old rats from their mothers and then counted the number of times they cried out in the "ultrasonic (超声波的) range", the frequen?cies higher than humans can hear,over five minutes. While both sexes called out hundreds of cries,the males called out twice as often,they found. But when the pups were returned to their mother's cage,she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocal calls showed the male pups had up to twice as much FoxP2 protein as the females. The research?ers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast,males became less talkative.

  The researchers then tested samples from ten children,aged between three and five,which showed that females had up to 30 per cent more of the FoxP2 pro?tein than males,in a brain area key to language in humans.

  "Based on our observations,we assume higher levels of FoxP2 in girls and higher levels of FoxP2 in male rats is an indication that FoxP2 protein levels are as?sociated with the more communicative sex," said Professor McCarthy.

  "Our results imply FoxP2 as a component (成分) of the neurobiological basis of sex differences in vocal communication in mammals."

1. From the second paragraph,we can learn that         .

   A. women always speak more words than men

   B. men and male rats have low levels of language protein

   C. women and male rats have similar levels of FoxP2

   D. McCarthy isn't the first to find females more talkative

2. The underlined phrase " fussed over" in the third paragraph probably means      

   A. paid attention to   B. related to

   C. put pressure on   D. counted on

3. The researchers carried out the experiments on rats in order to         .

   A. test which part of the brain is key to language in rats and humans

   B. prove the levels of FoxP2 protein in humans and rats are different

   C. determine the reason why female rats are more talkative than male rats

   D. discover the association between FoxP2 protein and vocal communication

4. Which of the following can be the best title for the passage?

   A. Tests on humans and rats   B. Why women are the talkative sex

   C. Sex differences in FoxP2 protein  D. FoxP2 protein determines oral ability

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