首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
学历提升
space is a dangerous place , not only because of meteors but also because of ...
space is a dangerous place , not only because of meteors but also because of ...
admin
2020-12-24
15
问题
space is a dangerous place , not only because of meteors but also because of rays from the sun and other stars.The atmosphere again acts as our protective blanket on earth.Light gets through , and this is essential for plants to make the food which we eat.Heat , too ,makes our environment endurable.Various kinds of rays come through the air from outer space , but enormous quantities of radiation from the sun are screened off.As soon as men leave the atmosphere they are exposed to this radiation.But their spacesuits or the walls of their spacecraft ,if they are inside , do prevent a lot of radiation damage.
Radiation is the greatest known danger to explorers in space.The unit of radiation is called “rem”.scientists have reason to think that a man can put up with far more radiation than 0.1 rem, without being damaged; the figure of 60 rems has been agreed on.The trouble is that it is extremely; difficult to be sure about radiation damage—a person may feel perfectly well , but the cells of his or her sex organs may be damaged , and this will not be discovered until the birth of deformed (畸形的) children or even grandchildren.Missions of the Apollo flights have had to cross belts of high radiation and , during the outward and return journeys, the Apollo crew accumulated a large amount of rems.So far , no dangerous amounts of radiation have been reported , but the Apollo missions have been quite short.We simply do not know yet how men are going to get on when they spend weeks and months outside the protection of the atmosphere , working in a space laboratory.Drugs might help to decrease the damage done by radiation , but no really effective ones have been found so far.
47.The best title for this passage would be( ).
选项
A.The Atmosphere and Our Environment
B.Research on Radiation
C.Effects of Space Radiation
D.Importance of Protection Against Radiation
答案
C
解析
通读全文可知,文章开头提到,宇宙空间里存在很多辐射,第二段又紧紧围绕辐射对人类的影响展开论述。C项符合题意,故选C。
转载请注明原文地址:https://ti.zuoweng.com/ti/RFVCKKKQ
相关试题推荐
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
spaceisadangerousplace,notonlybecauseofmeteorsbutalsobecauseof...
随机试题
关于认股权证,下列论述不正确的是()。 A、认股权证也称为股本权证 B、认股
螺旋扫描中,下列有关准直与有效层厚的描述,正确的一项是 A.实际层厚与准直宽度
2018年5月,甲公司成立,领取了工商营业执照、银行开户许可证、土地使用证和房屋
“严禁任何组织和个人向未成年人出售、出租或者以其他方式传播淫秽、暴力、凶杀、恐怖
《中国药典》(2010年版)的内容分为
净额结算的缓释作用主要体现为消除违约风险暴露。()
政府为了治理通货膨胀实行冻结物价的举措属于()。A.法律手段B.经济手段C.行政手段D.市场手段
我国封闭式基金的交收同A股一样实行()交割、交收。A.T+1B.T-1C.T+2D.T-2
患儿女,生后6小时出现四肢发凉,全身欠温,小腿、臀、臂、面颊等部位皮肤僵硬不能捏起,部分皮肤色紫发暗,面色晦暗,唇舌暗红,体温28℃。 治疗所选方药为A.金匮
能有效杀灭厌氧菌而对兼性厌氧菌无效的是A.四环素B.甲硝唑C.螺旋霉素D.罗红霉素E.环孢素