题目内容
Research into DNA has had a significant impact on medicine. Through recombinant DNA technology, scientists can modify microorganisms so that they become so-called factories that produce large quantities of medically useful drugs. This technology is used to produce insulin, which is a drug used by diabetics, and interferon, which is used by some cancer patients. Studies of human DNA are revealing genes that are associated with specific diseases, such as breast cancer. This information is helping physicians to diagnose various diseases, and it may lead to new treatments. For example, physicians are using a technology called chimeriplasty, which involves a synthetic molecule containing both DNA and RNA strands, in an effort to develop a treatment for a form. of hemophilia.
Forensic science uses techniques developed in DNA research to identify individuals who have committed crimes. DNA from semen, skin, or blood taken from the crime scene can be compared with the DNA of a suspect, and the results can be used in court as evidence.
DNA has helped taxonomists determine evolutionary relationships among animals, plants, and other fife forms. It is useful for this purpose, because closely related species have more similar DNA than do species that are distantly related. One surprising finding to emerge from DNA studies is that vultures of the Americas are more closely related to storks than to the vultures of Europe, Asia, or Africa.
Techniques of DNA manipulation are used in farming, in the form. of genetic engineering and biotechnology. Strains of crop plants to which genes have been transferred may produce higher yields and may be more resistant to insects. Cattle have been similarly treated to increase milk and beef production, as have hogs, to yield more meat and less fat.
Despite the many benefits offered by DNA technology, some critics argue that its development should be monitored closely. One fear raised by such critics is that DNA fingerprinting could provide a means for employers to discriminate against members of various ethnic groups. CritiCs also fear that studies of people' s DNA could permit insurance companies to deny health insurance to those people at risk for developing certain diseases.
The use of DNA technology in agriculture has also sparked controversy. Some people question the safety, desirability, and ecological impact of genetically altered crop plants. In addition, animal rights groups have protested against the genetic engineering of farm animals.
Despite these and other areas of disagreement, many people agree that DNA technology offers a mixture of benefits and potential hazards. Many experts also agree that an informed public can help assure that DNA technology is used wisely.
The author wants to tell us in Para. 1～4______.
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There is an allegation that______.
Print publications have lots of advantages. Paper is pleasant to handle, ready to read, and very portable: you can read it almost anywhere. On the other hand, print has its weaknesses. Paper is expensive, and articles are often cut to fit the space available. Printing and distributing paper is expensive and takes time. Printed materials are expensive to store and almost impossible to search. Electronic publishing offers solutions to all these problems.
Suppose a publisher makes the electronic copy of a newspaper or magazine available from the net, perhaps on the Internet's World Wide Web. No paper is used and disc space is cheap, so Internet publishing costs very little. Articles don't have to be cut. Internet publishing is fast, and readers can access material as soon as it becomes available: within minutes, instead of the next day, next week or next month. Internet publishing goes beyond geographical boundaries: the humblest local paper can be read everywhere from New York to London to Delhi to Tokyo. Delivery costs are low because there are no newsagents to pay, and no postal charges: readers pick up the hills for their on-line sessions. Also, eomputer-based publications axe simple to store and every word can be searched electronically.
At the moment, newspapers and magazines, TV and radio stations, news agencies and book publishers are making content freely available on the Web because they are competing for "mindshare". Perhaps they want to find out if they can attract and hold an audience on line, or perhaps they're afraid of missing out because "everyone else is doing it". 13ut don't count on things staying that way. Polishers are not in business to lose money.
What does the author probably foresee？
SECTION C NEWS BROADCAST
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. At the end of each news item, you will be given 10 seconds to answer the questions.
听力原文： Exit polls in Israel show that Prime Minister Ariel Sharon' s unilateral disengagement plan from some Palestinian areas has been firmly rejected by his Liked Party. While Mr. Sharon has acknowledged defeat in Sunday's referendum, he says he has no intention of resigning.
The exit polls broadcast late Sunday showed that between 58 and 62 percent of Likud members voted against the prime minister's plan to pull out of the Gaza Strip and parts of the West Bank.
Observers say opponents of the plan were more motivated than Mr. Sharon's supporters. The Liked Central Elections Committee says that only about 40 percent of the nearly 200,000 members eligible to take part in the referendum actually cast ballots.
Besides Low-voter turnout, another factor that appeared to weigh against the prime minister was the killing on Sunday of a pregnant Israeli woman and her four daughters in an ambush by Palestinian gunmen in the Gaza Strip.
It is believed the killings prompted many previously undecided Liked voters to reject the plan.
What percentage of Likud voted against the Prime Minister's plan？
What is the main idea of the (last three paragraphs)？
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