首页
登录
职称英语
Large animals that inhabit the desert have evolved a number of adaptations f
Large animals that inhabit the desert have evolved a number of adaptations f
游客
2025-03-18
10
管理
问题
Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. One adaptation is to be light in color, and to reflect rather than absorb the Sun’s rays. Desert mammals also depart from the normal mammalian(哺乳动物的)practice of maintaining a constant body temperature. Instead of trying to keep down the body temperature deep inside the body, which would involve the expenditure of water and energy, desert mammals allow their temperatures to rise to what would normally be fever height, and temperatures as high as 46 degrees Celsius have been measured in Grant’s gazelles. The overheated body then cools down during the cold desert night, and indeed the temperature may fall unusually low by dawn, as low as 34 degrees Celsius in the camel. This is an advantage since the heat of the first few hours of daylight is absorbed in warming up the body, and an excessive buildup of heat does not begin until well into the day.
Another strategy of large desert animals is to tolerate the loss of body water to a point that would be fatal for nonadapted animals. The camel can lose up to 30 percent of its body weight as water without harm to itself, whereas human beings die after losing only 12 to 13 percent of their body weight. An equally important adaptation is the ability to replenish(补充)this water loss at one drink. Desert animals can drink prodigious(巨大的)volumes in a short time, and camels have been known to imbibe over 100 liters in a few minutes. A very dehydrated person, on the other hand, cannot drink enough water to dehydrate at one session, because the human stomach is not sufficiently big and because a too rapid dilution(稀释)of the body fluids causes death from water intoxication. The tolerance of water loss is of obvious advantage in the desert, as animals do not have to remain near a water hole but can obtain food from grazing sparse and far-flung pastures. Desert-adapted mammals have the further ability to feed normally when extremely dehydrated: it is a common experience in people that appetite is lost even under conditions of moderate thirst.
Questions: [br] Why does the author mention humans in the second paragraph?
选项
A、To show how they use camels.
B、To contrast them to desert mammals.
C、To give instructions about desert survival.
D、To show how they have adapted to desert life.
答案
B
解析
转载请注明原文地址:http://tihaiku.com/zcyy/4002339.html
相关试题推荐
LivinginthecentralAustraliandeserthasitsproblems,______obtainingwater
Thenumberofregisteredcandidatesforthisyear’sentranceexaminationtomast
Manypeoplethinkofdesertsas______regions,butnumerousspeciesofplantsand
Largeanimalsthatinhabitthedeserthaveevolvedanumberofadaptationsf
Largeanimalsthatinhabitthedeserthaveevolvedanumberofadaptationsf
Largeanimalsthatinhabitthedeserthaveevolvedanumberofadaptationsf
Largeanimalsthatinhabitthedeserthaveevolvedanumberofadaptationsf
Woman:WhatamemoryIhave!Ididwritedownthenumberonasheetofpaperwhe
Humanbeingsactinadifferentwayfromthatofanimalsjustbecausetheyc
Theprincipalreasonforthegreatnumberofsmokeisthattherearetoomanyfa
随机试题
ScienceWithoutBordersScienceandtechnologyisamong
Mostmenliveinharness.Richardwasoneofthem.Typicallyhehadnoaware
Forthispart,youareallowed30minutestowriteacompositiononthetopic
下列哪种贫血,网织红细胞增高最明显A.巨幼细胞性贫血 B.慢性失血性贫血 C
缺铁性贫血的病因包括( )。A.铁消耗增加 B.膳食铁摄入不足 C.铁吸收
资信评级机构负责证券评级业务的高级管理人员,要求最近()年未因违法经营受到行政
患者,男,38岁,突发右下腹剧痛1小时,腹痛剧烈辗转不安,自我诊断为“急性阑尾炎
()对于网络相当于运输对于() A.电脑;货物 B.流量;交通 C.交流;
(2017年真题)个人经营贷款的担保机构存在()情况的,银行应暂停与该担保机构
武汉C公司是一家制造型企业,主打产品小家电。由于C公司有一整套的生产过程检测体系
最新回复
(
0
)