首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Every living thing has what scientists call a biological clock that controls behavior. It tells plants when to【C1】______flowers
Every living thing has what scientists call a biological clock that controls behavior. It tells plants when to【C1】______flowers
admin
2013-06-02
11
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 the 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 Siberain 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 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 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. It can【C16】______many days for a human body to【C17】______the 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】______.
【C15】
选项
A、can
B、must
C、might
D、may
答案
B
解析
语义衔接题。人们更换工作时间一般是迫不得已而为之,只有[B]must有这层含义,故为答案。
转载请注明原文地址:https://kaotiyun.com/show/HP67777K
0
大学英语六级
相关试题推荐
Don’tworry,behappyand,accordingtoanewresearch,youwillalsobehealthy.Itisestimatedthatoverthecourseofon
CreaturesoftheThermal(热量的)VentsThethree-personsubmersibleAlvinsankthroughthecold,darkwatersofthePacificOc
A、Becausehecouldmakebigmoneybydoingthis.B、Becauseheoncewashelpedbyastrangeronhighway.C、Becausepeoplewouldh
Peoplehavedreamedoftravelinginspaceforthousandsofyears.Butitwasnotuntil1957thatitbecamea(36)______.OnOcto
A、medicalschoolstudentsB、businessesandmanufacturesC、politicalcampaignparticipantsD、actors,techniciansandothersC
Anotherculturalaspectofnonverbalcommunicationisonethatyoumightnotthinkabout:space.Everyperson【B1】______himself
TheUniversityLibraryisoneofthelargest【B1】______librariesinthecountry,witha【B2】______ofsometwomillionvolumes.
Whatimpactcanmobilephoneshaveontheirusers’health?Manypeopleworryaboutthesupposedilleffectscausedbyradiation
InAmericanhighschoolstoday,it’stakenasagiventhatextracurricular(课外的)activitiesbringstudentsofdifferentracesto
FlirtWithSuicideThelifeofDavidWoodswasthestuffofanAustralianboy’sdream.Heplayedprofessionalrugbyleaguef
随机试题
消化道平滑肌对下列哪项刺激不敏感?
下列关于临界胶束浓度的叙述中正确的是()
"亢则害,承乃制"说明了五行之间的
上颌第二、第三磨牙的牙体长轴
属于化学药与中成药配伍禁忌的是
关于法院可以在诉讼中主动依职权采取的措施中,下列说法正确的是:()
法律格言说:“不知自己之权利,即不知法律。”关于这句法律格言涵义的阐释,下列哪一选项是正确的?(2010年卷一6题)
下列有关具体审计目标的说法中,正确的有()。
“走出去”战略是我国发展的根本基点。()
The"formallearning"referstoalllearningwhichtakesplaceintheclassroomregardlessofwhethersuchlearningis______byc
最新回复
(
0
)