首页
登录
职称英语
[originaltext] To us, the environment in which fish dwell often seems cold,
[originaltext] To us, the environment in which fish dwell often seems cold,
游客
2023-08-17
19
管理
问题
To us, the environment in which fish dwell often seems cold, dark and mysterious. But there are advantages to living in water.(22)And they’ve played an important role in making fish what they are. One is that water isn’t subject to sudden temperature changes. Therefore it makes an excellent habitat for a cold blooded animal. Another advantage is the water’s ability to easily support body weight. Protoplasm has approximately the same density as water. So a fish in water is almost weightless. This weightlessness in turn means two things:
1)A fish can get along with a light weight and a simple bone structure. And
2)Limitations to a fish’s size are practically removed.(20)Yet there is one basic difficulty to living in water—the fact that it is incompressible. For a fish to move through water, it must actually shove it aside.(21)Most can do this by wiggling back and forth in snake-like motion. The fish pushes water aside by the forward motion of its head and with a curve of its body and its flexible tail. Next the water flows back along the fish’s narrowing sides, closing in at the tail and helping the fish propel itself forward. The fact that water is incompressible has literally shaped the development of fish. A flat and angular shape can be moved through water only with difficulty. And for this reason, fish have a basic shape that is beautifully adapted to deal with this peculiarity.
20. What does the speaker mention as a problem that water presents to fish?
21. The speaker compares a fish’s movement with that of what creature?
22. What is the talk mainly about?
选项
A、A comparison of fish to warm-blooded animals.
B、The difference between saltwater and freshwater environments.
C、The importance of fish to human beings.
D、How water has affected the development of fish.
答案
D
解析
由“And they’ve played an im—portant role in making fish what they are.”可知本讲座内容为水是如何影响鱼的发展的。所以答案选D)。
转载请注明原文地址:https://www.tihaiku.com/zcyy/2935022.html
相关试题推荐
[originaltext]W:Thankyou,thankyouandwelcometoeveryone’sfavoritegames
[originaltext]W:Hmm,hi.M:Hi,Iamgoingdoortodoortonighttotellpeople
[originaltext]W:Hmm,hi.M:Hi,Iamgoingdoortodoortonighttotellpeople
[originaltext]M:IfIeverseethatguyagain,I’mdefinitelygoingtotellhim
[originaltext]M:IfIeverseethatguyagain,I’mdefinitelygoingtotellhim
[originaltext]M:IfIeverseethatguyagain,I’mdefinitelygoingtotellhim
[originaltext]M:IfIeverseethatguyagain,I’mdefinitelygoingtotellhim
[originaltext]WhenMidoriwastwoyearsold,sheoftenclimbedontothepia
[originaltext]WhenMidoriwastwoyearsold,sheoftenclimbedontothepia
[originaltext]WhenMidoriwastwoyearsold,sheoftenclimbedontothepia
随机试题
[originaltext]B:So,IpitchedtheideaforTOUCHtoMLBProperties,partnered
WriteonANSWERSHEETTHREEanoteofabout50-60wordsbasedonthefollo
提到中国体育不能不说乒乓球。乒乓球为中国赢得了无数个世界冠军(championship),给国人带来无穷的喜悦与自豪感。此外,乒乓球一直是中国人最喜爱的
经济全球化可以具体划分为()。A.贸易全球化 B.生产全球化 C.金融全球化
游客在旅游中期阶段的心理是()A:求安全心理 B:求全心理 C:懒散心态
银行应当建立有效的考评管理机制,注重绩效考评的过程和质量管理,强化绩效考评政策和
做胆管造影检查的患者,应采取的体位是A.胸膝卧位 B.去枕仰卧位 C.头低足
19世纪末的美国传教士雅瑟·亨·史密斯在《中国人的性格》中称中国人是“漠视时间的
下列不属于财务信息的是()。A.客户的收支情况 B.社会保障信息 C.资产与
重大事故的应急救援工作危险性极大,在编制应急预案时必须对应急人员自身的安全问题进
最新回复
(
0
)