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
2024-04-12
48
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://tihaiku.com/zcyy/3551282.html
相关试题推荐
[originaltext]We’vejustseentwocontemporarylargebirdsthatcannotfly—
[originaltext](20)In1871thefirstpassengerelevatorswereusedinoffic
[originaltext](16)Ineedtomakesureyouunderstandhowtogethousingfo
[originaltext](16)Ineedtomakesureyouunderstandhowtogethousingfo
[originaltext](12)Firstaidmaybedefinedastheimmediateandtemporary
[originaltext](12)Firstaidmaybedefinedastheimmediateandtemporary
[originaltext]IfyouareinanymajorcityinAmerica,thechancesarehigh
[originaltext]IfyouareinanymajorcityinAmerica,thechancesarehigh
[originaltext]IfyouareinanymajorcityinAmerica,thechancesarehigh
[originaltext]W:Hi,Peter,Iknowyouareagreatfanofsports,right?M:Ye
随机试题
[originaltext]W:Right,Iguessyouhavesomeideasforourpromotion.M:Well,
The"fatherofwaters",theMississippiRiverisoneofthe【C1】______inth
[originaltext]M:Don’tyourecognizeme,Jean?I’mTom,TomGreen.W:TomGree
关于错报,下列说法中正确的是( )。A、如果错报单独或汇总起来未超过财务报表整体
社会工作的“生态模型”强调社会工作实务的干预焦点是将个人置于()。A.其生活的
1998-131.营分证候的病机特点是 A.营阴受损B.津液耗竭C.心神
战某打电话向牟某借款5万元,并发短信提供账号,牟某当日即转款。之后,因战某拒不还
(2021年真题)我国货币供应量指标中,狭义货币供应量由流通中货币和()构成。
生产经营企业是安全生产的主体,对本单位安全生产负全面责任。根据安全生产相关法律法
超五类双绞电缆与普通五类双绞电缆相比,具有()的特点。A.最大衰减小,近端串音衰
最新回复
(
0
)