正文

2013年全国职称英语考试理工类押题试卷(4)

2013-03-22来源:和谐英语

　　第6部分：完形填空(第51～65题，每题1分，共15分)

　　下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。

　　A Biological Clock

　　Every living thing has what scientists call a biological clock that controls behavior. The biological clock tells ______ (51) when to form flowers and when the flowers should open. It tells ______ (52) when to leave the protective cocoons and fly away, and it tells animals and human beings when to eat, sleep and wake.

　　Events outside the plant and animal ______ (53) the actions of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its fur ______ (54) the number of hours of daylight. In the short ______ (55) of winter, its fur becomes white. The fur becomes gray brown in color in the longer hours of daylight in summer.

　　Inner signals control other biological clocks. German scientists found that some kind of internal clock seems to order birds to begin their long migration______ (56) twice each year. Birds ______ (57) flying become restless when it is time for the trip. ______ (58) they become calm again when the time of the flight has ended.

　　Scientists say they are beginning to learn which ______ (59) of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brain ______ (60) to control the timing of some of our actions. These ______ (61) tell a person when to ______ (62), when to sleep and when to seek food. Scientists say there probably are other biological clock cells that control other body activities.

　　Dr. Moorhead is studying ______ (63) our biological clocks affect the way we do our work. For example, most of us have great difficulty if we must often change to different work hours.

　　______ (64) can take many days for a human body to accept the major change in work hours. Dr.Moorhead said industrial officials should have a better understanding of biological clocks and how they affect workers. He said ______ (65) understanding could cut sickness and accidents at work and would help increase a factory’s production.

　　51. A. scientists B. humans C. plants D. animals

　　52. A. insects B. birds C. fish D. snakes

　　53. A. effect B. affect C. effected D. affected

　　54. A. because B. for the reason that C because of D. since

　　55. A. months B. days C. minutes D. weeks

　　56. A .flight B. fly C. movement D. transportation

　　57. A. prevented from B. ordered by C. helped by D. intruded on

　　58. A. and B. but C. therefore D. however

　　59. A. portions B. parts C. sections D. kinds

　　60. A. try B. tries C. seem D. seems

　　61. A. things B. parts C. cells D. actions

　　62. A. awaken B. woke C. awakening D. wake-up