首页
登录
从业资格
Passage 1 Plants and animals that have
Passage 1 Plants and animals that have
最全题库
2022-08-02
62
问题
Passage 1Plants and animals that have been studied carefully seem to have built-in clocks. These biological clocks, as they are called, usually are not quite exact in measuring time. However, they work pretty well because they are "reset" each day, when the sun comes up.Do pigeons use their biological clocks to help them find directions from the sun? We can keep pigeons in a room lit only by lamps. And we can program the lighting to produce artificial "days",different from the day outside. After a while we have shifted their clocks. Now we take them far away from home and let them go on a sunny day. Most of thegn start out as if they know just which way to go, but choose a wrong direction. They have picked a direction that would be correct for the position of the sun and the time of day according to their shifted clocks.It is known and experimented that homing pigeons can tell directions by the sun. But what happens when the sky is darkly overcast by clouds and no one can see where the sun is? Then the pigeons still find their way home. The salne experiment has been repeated many times on sunny days and the result was always the same. But on very overcast days clock-shifted pigeons are just as good as normal pigeons in starting out in the right directions. So it seems that pigeons also have some extra sense of direction to use when they cannot see the sun.Naturally, people have wondered whether pigeons might have a built-in compass—something that would tell them about the directions of the earth's magnetic field. One way to test that idea would be to see if a pigeon's sense of direction can be fooled by a magnet attached to its back.With a strong magnet close by, a compass can no longer tell direction.To test the idea, a group of ten pigeons had strong little magnet bars attached to their backs.Another group carried brass bars instead which were not magnetic. In a number of experiments,both groups were taken away from home and let go. On sunny days none of the magnet-pigeons was fooled. They were just as good as the brass-pigeons in starting out in the right direction toward home. On cloudy, overcast days, however, with no sun the brass-pigeons chose the right direction,but the magnet-pigeons were in trouble. They later started out in different directions and acted completely lost.How can people shift pigeons' biological clocks?查看材料A.By training them when they are young.B.By minor and harmless operations.C.By taking them really far away from home.D.By keeping them in artificial days.
选项
A.By training them when they are young.
B.By minor and harmless operations.
C.By taking them really far away from home.
D.By keeping them in artificial days.
答案
D
解析
根据第二段中“And we can program the lighting to produce artificial‘days’,different from the day outside.After a while we have shifted their clocks."可以得知D项正确。
转载请注明原文地址:https://tihaiku.com/congyezige/1878498.html
本试题收录于:
中学英语学科知识与教学能力题库教师资格笔试分类
中学英语学科知识与教学能力
教师资格笔试
相关试题推荐
请阅读Passage2,完成小题: Passage2Americans
请阅读Passage1,完成小题。 Passage1Ofallthe
Mendifferfromanimals______theycan
Thepassagemustprobablyappearsin____
Howdoestheauthororganizethepassage
Passage1 Inatraditionalclassroom,
Passage1 Inatraditionalclassroom,
Passage2 FormostAmericankids,itwo
Passage2 FormostAmericankids,itwo
Passage2 FormostAmericankids,itwo
随机试题
困扰bother;disturb
干粉灭火器扑救固体可燃物火灾时,应对准燃烧()喷射,并上下、左右扫射。A.火焰
劳务管理资料档案文件记录类最低保存年限8年。
对冬季温度低、且低温持续时间长的地区,或者重载交通较少的路段,宜选用细型密级配沥
子宫内膜癌的发生可能与下述哪一类激素有关A.孕激素 B.雄激素 C.雌激素
共用题干 OrganDonationandTransplantation
1994-44.半夏厚朴汤的功用是 A.行气降逆,燥湿化痰B.疏肝散结,燥湿
在垄断资本主义阶段,成为资本主义国家政治、经济和社会生活等方面实际统治者的是(
急性心包炎心电图变化多有ST段抬高,其中最常见的是哪种心包炎A、化脓性 B、结
(2016年真题)某网络计划中,已知工作M的持续时间为6天,总时差和自由时差分别
最新回复
(
0
)