2. 外语
  3. Research into DNA has had a significant impact on medicine. Through recombinant DNA technology, scientists can modify microorgan

Research into DNA has had a significant impact on medicine. Through recombinant DNA technology, scientists can modify microorgan

admin2010-05-14  41
问题    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 life 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______.
选项 A、DNA’ s functions
B、DNA’ s applications
C、DNA’ s research
D、DNA’ s techniques
答案B
解析 前四段主要讲了DNA在医学、法律等方面的使用，故选B。
转载请注明原文地址:https://jikaoti.com/ti/ju4YFFFM
0

专业英语八级

相关试题推荐
随机试题
最新回复(0)