首页
登录
职称英语
Every living thing has what scientists call a biological clock that control
Every living thing has what scientists call a biological clock that control
游客
2024-05-30
34
管理
问题
Every living thing has what scientists call a biological clock that controls behavior. It tells plants when to【C1】______ flowers and insects when to leave protective cocoon (茧)and fly away. And it tells animals and human beings when to【C2】______ , sleep and seek food. It controls our body temperatures, the【C3】______ of some hormones and even dreams.
Events【C4】______ the plant and animal affect its actions. Scientists recently found that a tiny animal called Siberian hamster changes the color of its【C5】______ because of the number of hours of【C6】______ . In shorter days of winter its fur becomes white. The fur becomes gray-brown in longer【C7】______ of daylight in summer.
【C8】______signals control other biological clocks. German scientists found that some internal one seems to order birds to begin their【C9】______ flights two times each year. Birds prevented from flying become【C10】______ when it is time for the trip.【C11】______ they become calm again when the time of the flight has ended. A mix of outside and internal events controls some biological clocks; such things as heartbeat and the daily change from sleep to walking take place because of both external and internal signals.
Scientists are beginning to learn【C12】______ parts of the brain contain the biological clocks. A researcher at Harvard University, Dr. Martin Moore Ede, said a small group of cells near the front of the brain seemed to control the【C13】______ of some of our actions. Probably there are other cells to control other body activities. He is studying【C14】______ they affect the way we do our work. Most of us have great difficulty if we【C15】______ often change to different work hours.【C16】______ can take many days for a human body to【C17】______ a major change in work hours. Industrial officials should have a better【C18】______ of biological clocks and how they affect workers. He said such an understanding could【C19】______ sickness and accidents at work, and would help increase【C20】______ . [br] 【C15】
选项
A、may
B、can
C、must
D、might
答案
C
解析
情态动词辨析题。情态动词的使用应该参照语境。人们更换工作时间一般是迫不得已而为之,因此只有等到必须做的时候才会更换。must表示“必须”,所以C正确。
转载请注明原文地址:http://tihaiku.com/zcyy/3612173.html
相关试题推荐
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
Everylivingthinghaswhatscientistscallabiologicalclockthatcontrol
随机试题
Atthe_______ofthelecture,I’dliketothankyouforyourpresence.(begin)be
Everyyear,theNobelPrizeisgiventooutstandingworkinsixfields:phys
WillaCather’sworksincludethefollowingsEXCEPTA、MyAntonia.B、TheSongofth
Therearetwomajorproblemswithmemory—storageandretrieval.【C1】______th
AscientificpanelconvenedbytheWorldHealthorganizationrecommendedgui
下列消防水泵的组件中不正确的是()。A.叶轮 B.泵轴 C.明杆闸阀 D
在行为改变外因中,不属于社会环境的内容是A.文化与教育 B.法律与法规 C.
A.23个 B.20个 C.44个 D.45个 E.67个足太阳膀胱经的
容易引起无意注意的刺激包括()多选A.强度大的刺激 B.突然出现的刺激
某工程设备安装阶段,需要使用起吊能力为10t的吊车进行大型永久设备的吊装。承包商
最新回复
(
0
)