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
A、Grows colder as the blubber accumulates. B、Remains the same. C、Varies according to the water temperature. D、Grows warmer as th
A、Grows colder as the blubber accumulates. B、Remains the same. C、Varies according to the water temperature. D、Grows warmer as th
admin
2013-07-01
43
问题
Millions of years ago, whales lived on land and walked on four legs. Today, whales still have small bones that are the remains of their hind legs, but these bones can only be seen on the inside of the whale. No one knows why whales left the land to live in the water.
However, scientists can imagine that when the whales changed their environment, their bodies underwent a change — taking on a more fish-like appearance. This new form offered less resistance to the water, enabling the whales to swim faster.
Despite their fish-like form, whales are not fish. A whale will drown, just as a man will, if it stays under water too long. When a whale is under water, it closes its nostrils tightly and holds its breath. The air in its lungs becomes very hot and full of water vapor. When the whale rises to the surface and exhales, its hot breath produces a column of water vapor that rises high in the air. A man produces the same effect when he exhales warm air on a cold morning.
Whales are classified as mammals because they bear their young, rather than laying eggs, and because the mother whales give the babies milk. Like other mammals, whales have warm blood. Their blood stays at the same temperature, even when they move from hot to cold water. They keep warm in cold water because they have a thick layer of fat just under their skins. This fat is called blubber, and it is thicker on whales that spend their lives in cold water. Almost all land mammals, except man, have hair on their bodies to keep them warm, but whales, which have very few hairs, are kept warm by their fat.
Questions:
33. How does a whale keep itself warm?
34. What do we learn about the blood temperature of a whale?
35. In what way do whales distinguish themselves from other land mammals?
选项
A、Grows colder as the blubber accumulates.
B、Remains the same.
C、Varies according to the water temperature.
D、Grows warmer as the whale grows older.
答案
B
解析
细节题。文中提到的Their blood stays at the same temperature,even when they move from hot to coldwater.(即使是从暖水游到冷水,它们的体温也保持不变。)表明,鲸的体温是恒定不变的,答案是B。
转载请注明原文地址:https://kaotiyun.com/show/lNn7777K
0
大学英语六级
相关试题推荐
NationalGuardtroopsareintendedbythepresidentto______.Theauthorofthispassageisprobably______.
A、Becauseitis22miles.B、Becausetheplanesturnsharply.C、Becauseofdrivingconditions.D、Becausetherearenosigns.C
Somestudentsarenotadequatelypreparedforcollege.Shouldweturnthemaway?【B1】______them?Ormodifyourproduct?Americ
A、Twoyears.B、Threeyears.C、Fiveyears.D、Eightyears.C本题问“谈话者结婚几年了”。这是一个细节题。答案在文章开头,正是因为“结婚五周年庆”引出了整个对话。故C项“五年”为正确答案。
A、StudentsworkingonadoctoralprogramwithaMaster’sdegreehavetenconsecutivesemesterstocompletetherequirements.B、
MostChineseAmericansworkedinrestaurantsandlaundriesbecauseof______.China’shighculturaltraditionsarerepresentedb
MostChineseAmericansworkedinrestaurantsandlaundriesbecauseof______.ChineseimmigrantstoHawaiifoundthatthey______
A、Theyaffectone’swayoflookingattheworld.B、Theymakepeoplefeellonelyandunwanted.C、Theyaffectone’shealthconditi
随机试题
A、Theurgencyofpensionreform.B、Medicalcareforseniorcitizens.C、Findingmeaningfulrolesfortheelderlyinsociety.D、Th
患者男性,27岁,气急,乏力,心绞痛,活动后晕厥,听诊胸骨左缘可闻及收缩中晚期粗糙的吹风样杂音,临床诊断为肥厚型梗阻性心肌病。下列哪些疾病属于继发性心肌病
《素问.阴阳应象大论》“治病必求于本”之“本”是指
如果可选用的炸药有32mm和25mm两种不同直径药卷,则以下正确的是()。
建设项目工程总承包方的项目管理目标包括()。
会计人员如有侵占企业财产,私分国有财产和罚没财产行为应当按照会计法的有关规定给予处罚。 ( )
下列属于非系统的绩效考核方法的是()。
下列各项中,综合性较强的预算是()。(2010年)
劳动教养的适用对象,是指实施了违法或轻微犯罪行为,依照劳动教养法律规定应当被劳动教养的人。()
一个33位的无符号二进制整数,化为十六进制数有______位。
最新回复
(
0
)