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
75
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
NarratorListentopartofalectureinahistoryclass.Nowgetr
[originaltext]W:HeyMike,gotasecond?M:Sure,what’sup?W:Theco
Nowwhicharetheanimalsreallytobepitiedincaptivity?First,thosecle
专利权人甲在其制造、销售的专利产品上未标注专利标记和专利号,某乙仿制甲上述专利产
某公司2016年营业收入为8000万元,平均资产总额为4000万元,该公司的总资
公司债券完成首期发行后,剩余数量应在( )发行完毕。 Ⅰ.自首期发行完成之日
下列各项,属瘀血内阻临床表现的是A.面色黧黑 B.面黑干焦 C.面黑浅
下列哪个不是肾上腺皮质激素A.米非司酮 B.醋酸泼尼松 C.倍他米松 D.
建设社会主义新农村是我国现代化进程中的重大历史任务.其要求是( ) A.生产
某女,26岁,带下量多、色黄,时有阴部瘙痒,经诊断为湿热瘀滞所致的带下病。医师所
最新回复
(
0
)