首页
登录
职称英语
Large animals that live in the desert have evolved a number of adaptations f
Large animals that live in the desert have evolved a number of adaptations f
游客
2024-02-24
48
管理
问题
Large animals that live in 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 (哺乳动物) also depart from the normal mammalian 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 (一种小羚羊). 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 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 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 non-adapted animals. The camel can lose up to 30 percent of its body weight as water with no 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 supply this water loss at one drink. Desert animals can drink great volumes in a short time, and camels have been known to take in over 100 liters in a few minutes. A very dehydrated (脱水) person, on the other hand, can not drink enough water to supply water at one session, because the human stomach is not sufficient big and because a too rapid dilution (稀释) of the body fluid causes death from water intoxication. The tolerance of water loss is of obvious advantage in the desert, as animals don’ t have to remain near a water hole but can obtain food from grazing sparse and far-flung natures. 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. [br] The internal temperature of a large desert mammal is lowest______.
选项
A、just before sunrise
B、just after sunset
C、just after drinking
D、in the middle of the day
答案
A
解析
本题测试文章细节。见第一段中间"the temperature may fall unusually low by dawn,"意为“黎明时体温最低”,与[A]项选择(just before sunrise)同义。
转载请注明原文地址:https://tihaiku.com/zcyy/3478623.html
相关试题推荐
TheEuropeanUnionhadapprovedanumberofgeneticallymodifiedcropsuntil
TheEuropeanUnionhadapprovedanumberofgeneticallymodifiedcropsuntil
TheEuropeanUnionhadapprovedanumberofgeneticallymodifiedcropsuntil
TheEuropeanUnionhadapprovedanumberofgeneticallymodifiedcropsuntil
TheEuropeanUnionhadapprovedanumberofgeneticallymodifiedcropsuntil
[originaltext]Manyanimalsareusedtohelpscientistsfindoutwhatwillh
Thepartnershipbetweenhumansandanimalsdatesbacktothefirstdomestica
Thepartnershipbetweenhumansandanimalsdatesbacktothefirstdomestica
Thepartnershipbetweenhumansandanimalsdatesbacktothefirstdomestica
Thepartnershipbetweenhumansandanimalsdatesbacktothefirstdomestica
随机试题
Iaskedsuccessfulpeoplewhatthesecretoftheirsuccesswas.I【B1】______a
Anintroductorysentenceforabriefsummaryofthepassageisprovidedbelow.C
[originaltext]M:Hey,Vale.Sinceyou’refromArgentina,I’dhavetoaskyouab
功效补脾养胃,生津益肺,补肾固涩的药物是()A.山药 B.太子参 C.
某基金总资产为50亿元,总负债为20亿元,发行在外的基金份数为30亿份,则该基金
无单独巡视设备资格的人员到变电站参观检查,应在()的陪同下方可进入设备场区
中国大陆第一部荣获柏林国际电影节“金熊奖”的电影是()。 A.《本命年》B.
()具有保证劳动法体系全面实施的功能。A.劳动法律法规制度 B.企业内部劳动
下列有关组织、强迫、引诱、容留、介绍卖淫罪,说法正确的是:()A.明知是淫秽网站
施工文件档案卷内的文字材料按事项、专业顺序排列、同一事项的请示与批复、同一文件的
最新回复
(
0
)