首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A pure virus(病毒) could be kept in a bottle, just like hundreds of other chemicals. Yet, when a virus is placed on a living thing
A pure virus(病毒) could be kept in a bottle, just like hundreds of other chemicals. Yet, when a virus is placed on a living thing
admin
2018-08-10
50
问题
A pure virus(病毒) could be kept in a bottle, just like hundreds of other chemicals. Yet, when a virus is placed on a living thing, it comes to life. As long as it is on a living material, it grows.
A difficult question still remains—what is a virus? Is it living or chemical? Men of science had always thought life and not-life to be as different as black and white. With the discovery of the virus, they became aware of
a grey area
that was neither black nor white.
Until the 1930’ s, it was accepted that there was also a great difference in size between the largest chemical molecules (分子) and the smallest living things. As new and much finer filters(过滤器) were invented, men were able to measure viruses. The first virus to be measured was found to be about 100 millimicrons(毫微米) across.
The largest known chemical molecule measures only 22 millimicrons. The smallest living thing measures almost seven times that size or 150 millimicrons. When viruses were measured, they were found to range in size from 16 millimicrons to 300 millimicrons. Most were found to be larger than the largest chemical molecules and smaller than the smallest living things.
The answer to the puzzle—what is a virus? —must be that it is both living and not living. In a living cell, it is a live thing. In a bottle, it is nothing more than a chemical. We now realize that the virus is actually a link between life and not-life.
What makes a virus come to life?
选项
A、A large chemical molecule.
B、A dead chemical.
C、An active virus.
D、A living cell.
答案
D
解析
细节题。题干意为“是什么让一个病毒有了生命?”。由文章第一段第二句“Yet,when a virus is placed on a living thing it comes to life.”可知病毒附着一个生命体上,病毒就是有生命的,一个有生命的细胞是一个生命体。故D为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/Fcrd777K
本试题收录于:
公共英语二级笔试题库公共英语(PETS)分类
0
公共英语二级笔试
公共英语(PETS)
相关试题推荐
—Wouldyoumindholdingthedooropenforme,please?—______.
Tonycouldn’tgotouniversitybut______hiseducationthrougheveningschoolcourses.
LatelyIhavebeennoticingthegreatnumberofelectricalappliances(电器)onthemarket.Itseemstomethatthereare(36)
Mr.Duffhadseveralfarmsinthevillage.He36someworkersandmadethemworkmorethantwelvehoursa37Hedidn’tsupplyth
Manypeoplemaketheirlivingwiththeirhands.Edmakeshislivingwithhisfeet.HeplayssoccerontheSantosteam.Heisth
Manypeoplemaketheirlivingwiththeirhands.Edmakeshislivingwithhisfeet.HeplayssoccerontheSantosteam.Heisth
Amandaiscarefulaboutanythingthattouchesherlips.She【C1】______instructionsoneveryfoodpackanddoesallshecanto【C
IrememberJimmyleft______arainynight.
Jimwasbornafterhiselderbrotherandsister.Hecouldlearnmanythingsfromthem.Soon,hedevelopedhisownwayofdoing
Peoplebuyittogetonatrainorintoapark.Itcarriespeopleandtravelsintheair.
随机试题
多重趋避式冲突是指人们面对着两个或两个以上的目标,而目标又各自分别具有吸引和排斥两方面的作用,人们无法简单地选择一个目标而回避或拒绝另一个目标时的矛盾心态。根据上述定义,下列体现多重趋避式冲突的是:
腰椎穿刺后6h内让患者采取去枕仰卧位的目的是
患者胃脘疼痛,如针刺刀割,痛有定处,按之痛甚,食后加剧,入夜尤甚,舌质紫暗有瘀斑,脉涩。其治法是
下列选项中,不属于生产经营单位的主要负责人对本单位安全工作负有的责任的是()。下列说法不正确的是()。
只要实现了期初余额、本期发生额和期末余额三栏的平衡关系,就说明账户的记录是正确的。()
以下哪项中的画作不是我国著名画家齐白石的作品?()
《智慧女神报》
[2008年]在下列微分方程中以y=C1ex+C2cos2x+C3sin2x(C1,C2,C3为任意常数)为通解的是().
设任意一个十进制整数D,转换成对应的无符号二进制整数为B,那么就这两个数字的长度(即位数)而言,B与D相比_______。
Schoolsthroughouttheworldareexperiencingaperiodofrapidchangeand,inmanycases,arefindingthatextremely【M1】______
最新回复
(
0
)