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
2018-05-03
54
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/mMrd777K
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
Morethan6000childrenwereexpelledfromUSschoolslastyearforbringinggunsandbombstoschool,theUSDepartmentofEduc
Ihavealways(36)goingtoschool.Ienjoylearningnewthingsand(37)newpeople.Itrytothinkofmyschoolwork(38
Ihavealways(36)goingtoschool.Ienjoylearningnewthingsand(37)newpeople.Itrytothinkofmyschoolwork(38
WhatareJohnandMarytalkingabout?
—Excuseme,haveyoueverbeentoSwitzerland?—______.Butmanypeoplesayit’saverybeautifulcountry.
AlmosteveryoneknowsthemeaningofMr.,Mrs.andMiss.Mr.isusedbeforethenamesofmen.Mrs.,isformarriedwomenandMis
WhenIwasalittlechildren,schoolwasa31.______beautifulgardentome.Tomyeyes,allthe
Centuriesago,mountainswerethoughttobethehomeofevilspirits,itwasnotuntil200yearsagothatmenbegantoclimbthe
ThePetronasTwinTowersinKualaLumpurinMalaysiawerecompletedin1998.Eachtoweris452metershighandhas88floors.De
[A]Ateight.[B]LiPingis.[C]Onlyafewkilometers.[D]Onlyone.[E]Aplane.[F]Yes,heis.
随机试题
企业使命
Sicknessdeprivedme______thechanceofseeingyou.
旅馆和公共建筑生活用水定额确定的依据是()
如果某项目生产经营期的第一年出现亏损,则该项目在此年可以免缴()。
( )是保险代理从业人员将代收保费的一部分交付所属机构,另一部分据为已有的行为。
《论语·为政》指出:“道之以政,齐之以刑,民免而无耻;道之以德,齐之以礼,有耻且格。”这一观点反映了()。
从幼儿在园一日活动的主要类型来分,幼儿园环境可分为游戏活动环境、学习活动环境和()。
下列关于生物遗传的叙述错误的是()。
Thedestructionofournaturalresourcesandcontaminationofourfoodsupplycontinuetooccur,largelybecauseoftheextreme
以下程序段运行结束后,变量x的值为()。x=2y=4dox=x*yy=y+1LoopWhiley
最新回复
(
0
)