Every living thing has what scientists call a biological clock that controls behavior. The biological clock tells ___C__1___ when to form flowers and when the flowers should open1. It tells ___A__2____ when to leave the protective cocoon and fly away, and it tells animals and human beings when to eat, sleep and wake.
Events outside the plant and animal ___B__3_____ the actions of some biological clocks. Scientists recently found, for example, that a tiny animal changes the color of its fur __C__4_____ the number of hours of daylight. In the short ____5__B_ of winter, its fur becomes white. The fur becomes gray brown in color in the longer hours of daylight 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 ___A__6____ twice each year. Birds ____A_7_____ flying become restless when it is time for the trip, _B___8___ they become calm again when the time of the flight has ended.
Scientists say they are beginning to learn which __B__9____ of the brain contain biological clocks. An American researcher, Martin Moorhead, said a small group of cells near the front of the brain __D__10____ to control the timing of some of our actions. These ___C_11____ tell a person when to ___A__12_____, 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 __A___13____ our biological clocks affect the way we do our work2. For example, most of us have great difficulty if we must often change to different work hours. ___B__14____ can take3 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 __C__15____ understanding could cut sickness and accidents at work and would help increase a factorys production.
1. A) scientists B) humans C) plants D) animals
2. A) insects B) birds C) fish D) snakes
3. A) effect B) affect C) effected D) affected
4. A) because B) for the reason that C) because of D) since
5. A) months B) days C) minutes D) weeks
6. A) flight B) fly C) movement D) transportation
7. A) prevented from B) ordered by C) helped by D) intruded on
8. A) and B) but C) therefore D) however
9. A) portions B) parts C) sections D) kinds
10. A) try B) tries C) seem D) seems
11. A) things B) parts C) cells D) actions
12. A) awaken B) wake C) awakening D) wake-up
13. A) how B) why C) where D) what
14. A) We B) It C) They D) You
15. A) so B) with C) such D) if
2015年2月英语六级听力备考精华笔记(2)
2015年2月英语六级听力高频词汇(6)
2015年2月英语六级听力解题九大猜测技巧(七)
2015年2月英语六级听力常考高频习语2
备考英语六级听力精听与泛听并行
2015年2月英语六级听力应试技巧五边处理法
大学英语六级听力练习bbc随身英语(9)
2015年2月英语六级听力怎样抓住关键词
英语六级改革后新题型样题及答案(听力)
2015年2月英语六级听力高频词汇(4)
2015年2月英语六级听力备考精华笔记(9)
六级答疑听力如何锻炼捕捉细节能力
英语六级备考阶段怎样做好听写
2015年2月英语六级听力常考高频习语1
2015年2月英语六级听力冲刺必备易混淆词汇(1)
大学英语六级听力技巧重在合理安排时间
2015年2月英语六级听力高频词汇(1)
2015年2月英语六级听力冲刺必备易混淆词汇(2)
2015年2月大学英语六级听力复习必备单词(2)
2015年2月英语六级听力备考精华笔记(8)
2015年2月英语六级听力复合式听写高分攻略
2015年2月英语六级听力备考精华笔记3
2015年3月英语六级听力练习VOA常速513
2015年2月英语六级听力高分答题技巧
英语六级听力冲刺提分六步走
英语六级听力重在提炼信息
2015年2月冲刺备考英语六级听力短文听写高分技巧
2015年2月大学英语六级听力易混淆词汇(1)
透析2015年3月英语六级听力新题型短文听写
备考方法英语六级听力听写
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |