【单选题】
阅读下面的短文，文中有15处空白，每处空白给出了4个选项，清根据短文的内容从4个选项中选择1个最佳答案。
Every living thing has what scientists call a biological clock that controls behavior. The biological clock{{U}} (1) {{/U}}plants when to form flowers and when the flowers should open. It tells insects when to{{U}} (2) {{/U}}the protective cocoon (防护卵袋) and fly away, and it tells animals and human beings when to eat, sleep and wake.
Events outside the plant and animals{{U}} (3) {{/U}}the action of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its fur because of the{{U}} (4) {{/U}}of hours of daylight. In the short{{U}} (5) {{/U}}of winter, its fur becomes white. The fur becomes gray brown in{{U}} (6) {{/U}}in the longer hours of daylight in summer.
Inner signals control other{{U}} (7) {{/U}}clocks. German scientists found that some kind of internal clock seems to order birds to begin their long migration{{U}} (8) {{/U}}twice each year,Birds{{U}} (9) {{/U}}from flying become restless when it is time for the trip,{{U}} (10) {{/U}}they become calm again when the time of the flight has endeD、
Scientists say they are beginning to learn which{{U}} (11) {{/U}}of the brain contain biological clocks.AnAmerican researcher, Martin Moorhead, said a small group of cells near the front of the brain{{U}} (12) {{/U}}to control the timing of some of our actions. These{{U}} (13) {{/U}}tell a person when to wake, when to{{U}} (14) {{/U}}, and when to seek fooD、Scientists say there probably are other biological clock cells that{{U}} (15) {{/U}}other body activities.
B．months
C．minutes
D．weeks
网考网参考答案：A
网考网解析：
[解析] 解题思路：备选项是否有关系(词义上相关)，注意借助空格处的搭配结构“在冬季里短的……里”判断答案A正确。 document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>
发布评论 查看全部评论