首页
登录
职称英语
Salt is as necessary to life as water. In many areas of Africa people once d
Salt is as necessary to life as water. In many areas of Africa people once d
游客
2024-01-19
68
管理
问题
Salt is as necessary to life as water. In many areas of Africa people once drank the urine(尿)of animals because they had no other source of salt. Without salt, human beings die.
The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys(肾)and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌)of water. In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst.
In cases where there is little or no water to drink, the body tries to do the opposite thing. Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body’ s normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant. [br] What does the word "constant"(Line 2, Para. 3)mean in the passage?
选项
A、The same.
B、Amount.
C、Going up and down.
D、Changing.
答案
A
解析
语义判断题。此空与动词keep构成系表结构,应为形容词成分,排除B选项。C、D选项同义,可排除。根据句意,血液中的盐分含量应保持恒定,选A。
转载请注明原文地址:http://tihaiku.com/zcyy/3376675.html
相关试题推荐
Childrenandoldpeopledonotlikehavingtheirdaily______upset.A、habitB、prac
Manypeoplefavor______morenuclearpowerplants.A、tobuildB、builtC、buildD、bu
Withoutthefriction(摩擦力)betweentheirfeetandtheground,peoplewould______b
Peoplehavebeenfondofrosessincethebeginningoftime.Infact,itiss
Peoplehavebeenfondofrosessincethebeginningoftime.Infact,itiss
Peoplehavebeenfondofrosessincethebeginningoftime.Infact,itiss
Peoplehavebeenfondofrosessincethebeginningoftime.Infact,itiss
Englishisusedbymorepeoplethanis______languageexceptChinese.A、anyB、any
Thefacesofelderly,happily-marriedpeoplesometimesresembleeachother
Thefacesofelderly,happily-marriedpeoplesometimesresembleeachother
随机试题
StudentexpeditionsdoagreatdealofgoodworkontheArcticislandsbutf
TheUNGeneralAssembly,thecentralpoliticalforum,iscomposedof193members
BuyingaNewCarDecideWhatYouCanAfford,Want,and
Ifyou’refindingittoughtolandajob,followahuntingplanwiththefol
某女,28岁。肘关节肌肉酸痛重着不移2个月,伴有肿胀,肌肤麻木不仁,阴雨天加重,
教师管理的根本问题是()。A.激励教师勤奋工作 B.营造和睦相处的氛围
根据《招标投标法实施条例》,投标人或者其他利害关系人认为招标投标活动不符合法律、
1.企业文化划分为()等几个层次。(A)行为文化(B)物质文化(
阅读下列史料并回答问题: 明太祖既定江左,鉴前代之失,置宦者不及百人。迨末年颁
眶下间隙感染向颅内扩散,并发海绵窦血栓性静脉炎,其扩散途径通常是()A.面前
最新回复
(
0
)