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 an inner biological clock that controls behavior. The clock works all the time even when there are no out
Every living thing has an inner biological clock that controls behavior. The clock works all the time even when there are no out
admin
2015-01-09
31
问题
Every living thing has an inner biological clock that controls behavior. The clock works all the time even when there are no outside signs to mark the passing of time. The biological clock tells plants when to form flowers and when the flowers should open. It tells insect when to leave the protective cocoon and fly away. And it tells animals when to eat,sleep and wake. It controls body temperature,the release of some hormones and even dreams. These natural daily events are circadian rhythms.
Man has known about them for thousands of years. But the first scientific observation of circadian rhythms was not made until 1729. In that year French astronomer,Jean-Jacquesd"Ortous de Mairan",noted that one of his plants opened its leaves at the same time every morning,and closed them at the same time every night. The plant did this even when he kept it in a dark place all the time. Later scientists wondered about circadian rhythms in humans. They learned that man’s biological clock actually keeps time with a day of a little less than 25 hours instead of the 24 hours on a man-made clock. About four years a-go an American doctor,Eliot Weitzman,established a laboratory to study how our biological clock works. The people in his experiments are shut off from the outside world. They are free to listen to and live by their circadian rhythms. Dr. Weitzman hopes his research will lead to effective treatments for common sleep problems and sleep disorders caused by aging and mental illness. The laboratory is in the Monte-flore Hospital in New York City. It has two living areas with three small rooms in each. The windows are covered,so no sunlight or moonlight comes in. There are no radios or television receivers. There is a control room between the living areas. It contains computers,one-way cameras and other electronic devices for observing the person in the living area. The instruments measure heartbeat,body temperature,hormones in the blood,other substances in the urine and brain waves during sleep. A doctor or medical technician is on duty in the control room 24 hours a day during an experiment. They do not work the same time each day and are not permitted to wear watches,so the person in the laboratory has no idea what time it is. In the first four years of research,Dr. Weitzman and his assistant have observed 16 men between the ages of 21 and 80. The men remained in the laboratory for as long as six months. Last month,a science reporter for The New York Times newspaper,Dava Sobol,became the first woman to take part in the experiment. She entered the laboratory on June 13th and stayed for 25 days. Miss Sobol wrote reports about the experiment during that time, which were published in the newspaper.
In his observation, the French scientist noticed that the leaves of a certain plant maintained its open-ing-and-closing cycles_____.
选项
A、even when it was kept in a murky place all day
B、even if it was placed in the moonlight
C、even when he was observing it from a dark place
D、even during the night time
答案
A
解析
细节题。第二段第三句话说“…that one of his plants opened its leaves at the same time everymorning,and closed them at the same time every night.The plant did this even when he kept it in adark place all the time.”这与A符合。
转载请注明原文地址:https://kaotiyun.com/show/MMQO777K
0
考博英语
相关试题推荐
Manyinstructorsbelievethataninformal,relaxedclassroomenvironmentis【C1】______tolearningandinnovation.Itisnotuncom
Iwillbrieflydiscussthebenefits_____Ifeelhaveresultedfromtheproject.
Fromchildhoodtooldage,wealluselanguageasameansofbroadeningourknowledgeofourselvesandtheworldaboutus.When
PresidentBushcametohisparent’scentury-oldsummerhomeontheMainecoastforalittlerelaxation,adistantcousin’sweddi
Businessandgovernmentleadersconsidertheinflationratetobeanimportantgeneralindicator.Inflationisaperiodofincre
Cancerhasalwaysbeenwithus,butnotalwaysinthesameway.Itscareandmanagementhavedifferedovertime,ofcourse,but
Itisnotoftenrealizedthatwomen【1】ahighplaceinsouthernEuropeansocietiesinthe10thand11thcenturies.Asa【2】,thew
Hersuccessfuljumpbroughta______cheerfromthecrowd.
Inmanycountriestobaccoandmedicinearegovernment______.
Theitemscontainedintheparceldon’tcorrespond______thoseonthelistthataccompaniedit.
随机试题
气门间隙的大小是怎样确定的?
盖碗的使用技巧,正确的有
槟榔的功效是
2007年8月13日,甲市防汛指挥部紧急征用了乙公司的库房并告知乙公司,但未给予任何经济补偿,乙公司提起行政诉讼期限在()届满。
[2012年第51题]动点以常加速度2m/s2做直线运动。当速度由5m/s增加到8m/s时,则点运动的路程为()。
控规设计质量的主要目的是( )。
水库在正常运用的情况下,允许消落到的最低水位称()。
欧洲封建社会形成的两种教育体系是()
In______,thetableofcontentsofthemagazinewasplacedonitsbackcover.Themagazinewascriticizedforfailingto
Largecompaniesneedawaytoreachthesavingsofthepublicatlarge.Thesameproblem,【B1】______,facespracticallyeverycom
最新回复
(
0
)