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
Scientists have established that influenza viruses taken from man can cause the disease in animals. In addition, man can catch t
Scientists have established that influenza viruses taken from man can cause the disease in animals. In addition, man can catch t
admin
2009-05-28
57
问题
Scientists have established that influenza viruses taken from man can cause the disease in animals. In addition, man can catch the disease from animals. In fact, a great number of wild birds seem to carry the virus without showing an evidence of illness. Some scientists concluded that a large family of influenza viruses may have evolved in the bird kingdom, a group that has been on the earth 100 million years and is able to carry the virus without contracting the disease. There is even convincing evidence to show that virus strains are transmitted from place to place and from continent to continent by migrating birds.
It’s known that two influenza viruses can recombine when both are present in an animal at the same time, the result of such recombination is a great variety of strains containing different H and N spikes. This raises the possibility that a human influenza virus can recombine with an influenza virus from a low animal to produce an entirely new spike. Research is underway to determine if that is the way that major new strains come into being, another possibility is that two animal influenza strains may recombine in a pig, for example, to produce a new strain which is transmitted to man.
选项
A、cause ill health in wild birds
B、do not always cause symptoms in birds
C、are rarely present in wild birds
D、change when transferred from animals to man
答案
B
解析
转载请注明原文地址:https://kaotiyun.com/show/TQvK777K
本试题收录于:
大学英语三级A级题库大学英语三级分类
0
大学英语三级A级
大学英语三级
相关试题推荐
A、Shehasgotadriver’slicense.B、Shewasacceptedbyacollege.C、Sheisgoingtoanothercountry.D、Shegotagoodjob.D从男士
Beforewecandecidewheretobuyourmaterials,werequireasmuchinformationaswecangetonthesuppliers.
HuaweiTechnologiesCo.,Ltd.HuaweiTechnologiesCo.,Ltd.isaChinesemultinationalnetworkingandtelecommunicationse
Thiscompanybringsabout30millionyuanineconomicbenefits(annual)______.
Businessmemoisfrequentlyusedincompanies.Itiscalledanintra-companycommunicationbecauseitisusedbypeopleintheir
Theproblems(discuss)______atthenationalmeetingyesterdayarevitaltothedevelopmentofthecountry.
InShanghai,agrowingnumberofforeign-fundedbanksarelookingforlocalpeopletofillexecutivepositions(行政主管的岗位)rather
I______myteachertowriteareferencelettertomeifIseeher.
Whydopeoplewanttosavethewhales?Becausetheyhelpto__________betweenplantsandanimals.
Whatwastheambitionofaneleven-year-oldboy?Theambitionofhimistobe______.
随机试题
下列哪项是内分泌系统中固有的内分泌腺
主动脉瓣关闭不全周围血管体征,下列哪项是错误的
关于产后出血的定义,哪项是正确的
A公司是甲国的公司,B公司是中国广州的一家公司,B公司是生产烟花爆竹的企业,该公司在2003年向A公司出口了一批烟花爆竹。后来,甲国公民C在使用B公司生产的烟花时,由于烟花突然改变方向,致使C左眼被炸伤。C在甲国法院以B公司为被告提出侵权之诉,要求B公司赔
2019年1月1日甲公司从乙公司租入一台需要安装的设备,根据该租赁合同确定的租赁负债的初始计量金额为100万元。设备租入后需要进行安装,领用原材料成本为8万元,公允价值为10万元。用银行存款支付的此项租赁合同的谈判和签订租赁合同过程中发生的初始直接费用为1
在各种账务处理程序下,其登记现金日记账的直接依据都是相同的。()
学生性格差异主要是指性格的_______和性格的类型差异。
一个人说话的内容不论如何精彩,但如果时机掌握不好,也无法达到说话的目的。因为听者的内心,往往随着时间变化而变化。要对方愿意听你的话,或者接受你的观点,都应当选择适当的时机。最能准确复述这段话主要意思的是( )
某系统总体结构如题6图所示。该系统结构图的最大扇出数是()
Howisnearsightednessaffectingtheworld?
最新回复
(
0
)