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
16
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、It can’t be compressed.
B、It is often polluted.
C、Its temperature often fluctuates dramatically.
D、It limits their size.
答案
A
解析
由“Yet there is one basic diffi—culty to living in water—the fact that it is in—compressible.”可知在水里生活的一个问题是无法压缩。所以答案为A)。
转载请注明原文地址:https://tihaiku.com/zcyy/3551280.html
相关试题推荐
[originaltext]Let’stalkaboutasocialconditionthatmanypeoplemightbe
[originaltext]Let’stalkaboutasocialconditionthatmanypeoplemightbe
[originaltext]Well,mytopictodayisthedoctor-patientrelationship.All
[originaltext]Well,mytopictodayisthedoctor-patientrelationship.All
[originaltext]Areyoufortyyearsoldandfat?Doyouwearfineclothes?Do
[originaltext]Areyoufortyyearsoldandfat?Doyouwearfineclothes?Do
[originaltext]Manystudieshavebeenmaderecentlyabouthandpreferencein
[originaltext]Manystudieshavebeenmaderecentlyabouthandpreferencein
[originaltext]M:Hi,Sue.IwaswonderingifyoucouldfillmeinonMonday’sc
[originaltext]M:Hi,Sue.IwaswonderingifyoucouldfillmeinonMonday’sc
随机试题
[originaltext]W:Well,Glyn,you’vebeencalledthefirstmalesupermodel.Woul
Alltheusefulenergyatthesurfaceoftheearthcomesfromtheactivityof
Gold(cancombined)withsilver(inany)proportion,butalloyswith50(to)60
女性,53岁,急性胰腺炎8天。超声检查如图所示,诊断为 A.胰腺假性囊肿 B
下列属于工程量计算依据的有()。A.国家.行业发布的工程量清单计价规范.工
一块1kg的土样,置放一段时间后,含水量由25%下降到20%,则土中的水减少了(
清算大致分为( )。 Ⅰ.账面价值清算 Ⅱ.重置全价清算 Ⅲ.破产清算
小学数学《长方体和正方体的表面积》 题目来源:5月18日上午天津市面试考
电缆通道、夹层内使用的临时电源应满足()要求,照明应良好。防高温$;$绝缘$;$
对本企业的安全生产负责的主体是建筑施工企业的()。A.法定代表人 B.总经理
最新回复
(
0
)