It happened one morning 20 years ago. A British scientist Alec Jeffrey came across DNA fingerprinting: He identified the patterns of genetic material that are unique to almost every individual. His di 题目和参考答案——青夏教育精英家教网—

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It happened one morning 20 years ago. A British scientist Alec Jeffrey came across DNA fingerprinting: He identified the patterns of genetic material that are unique to almost every individual. His discovery changed everything from the way we do criminal investigations to the way we decide family law. But the professor of genetics at the University of Leicester, UK, is still surprised, and a bit worried, by the power of the technology he released upon the world.

The patterns within DNA are unique to each individual, except identical twins, who share the same pattern. The ability to identify these patterns has been used to convict(证明…有罪) murderers and to clear people who are wrongly accused. It is also used to identify the victims of war and settle disputes over who is the father of a child.

Jeffrey said he and his colleagues made the discovery by accident while tracking genetic variations(变异). But, within six months of the discovery, genetic fingerprinting had been used in an immigration case, to prove that an African boy really was his parents’ son.·In 1986, it was used for the first time in a British criminal case: It cleared one suspect after being accused of two murders and helped convict another man.

DNA testing is now very common. In Britain, a national criminal database established in 1995 now contains 2.5 million DNA samples. The U.S. and Canada are developing similar systems. But there are fears about the stored DNA samples and how they could be used to harm a person’s privacy. That includes a person’s medical history, racial origin or psychological profile. “There is the long-term risk that people can get into these samples and start getting additional information about a person’s paternity(父子关系) or risk of disease,” Jeffrey said.

DNA testing is not an unfailing proof of identity. Still, it is considered a reasonably reliable system for determining the things it is used for. Jeffrey estimates the probability of two individuals’ DNA profiles matching in the most commonly used tests at one in a billion.

1.According to the text, DNA testing can NOT be used in _______ .

A. doing criminal investigations B. deciding faraily law

C. clearmg wrongly accused people D. telling twins apart

2.DNA samples are not popular with all the people because _______ .

A. the government in Britain establishes a criminal database

B. the US and Canada develop similar systems

C. DNA samples can be used to harm a person’s privacy

D. DNA testing is too expensive and dangerous now

3.Where will you most probably find this article?

A. In a guidebook. B. In a storybook.

C. In a science fiction. D. In a scientific magazine.

4.Which is the best title for the passage?

A. Discovery of DNA testing by Jeffery B. Practice of DNA testing in court

C. DNA testing in the present situation D.Benefits and side effects of DNA testing

【答案】

1.D

2.C

3.D

4.D

【解析】略

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Joe came to New York from the Middle West, dreaming about painting. Delia came to New York from the South, dreaming about music. Joe and Delia met in a studio. Before long they were good friends and got married.
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“Joe, , I’ve found a pupil, a general’s daughter. She is a sweet girl. I’m to give three lessons a week and get $5 a lesson.”
But Joe was not glad.
“But how about me?” he said.” Do you think I’m going to watch you work while I play with my art? No, I want to earn some money too.”
“Joe, , you are silly,” said Delia. “You must keep at your studies. We can live quite happily on $15 a week.”
“Well, perhaps I can sell some of my pictures,” said Joe.
Every day they parted in the morning and met in the evening. A week passed and Delia brought home fifteen dollars, but she looked a little tired.
“Clementina sometimes gets on my nerves. I’m afraid she doesn’t practice enough. But the general is the nicest old man! I wish you could know him, Joe.”
And then Joe took eighteen dollars out of his pocket.
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Next week Joe came home and put another eighteen dollars on the table. In half an hour Delia came, her right hand in a bandage.
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“Five o’clock, I think. The iron-I mean the soup-was ready about five, Why?”
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She began to cry.
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“And your pictures? Did you sell any to that man from Peoria?”
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A．a tutor

B．a music teacher

C．a laundry assistant

D．an artist

【小题2】It happened that .

A．a man from Peoria liked Joe’s pictures	B．Delia earned $15 dollars a week easily
C．Clemantina and the general were kind	D．the couple worked at the same laundry

【小题3】Who hurt Delia’s hand?

【小题4】We can infer from the underlined sentence that .

A．Clemantina was an invention of the general

B．Clemantina was an invention of the man from Peoria

C．the general, Clemantina and the man from Peoria were the couple’s clients

D．there were no such men as the general, Clemantina and the man from Peoria

【小题5】The couple’s attitude towards each other is .

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