首页
登录
职称英语
Scientists have established that influenza viruses taken from man can cause
Scientists have established that influenza viruses taken from man can cause
游客
2023-09-28
81
管理
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://tihaiku.com/zcyy/3053637.html
相关试题推荐
Manyfamousscientists______atthemeetingheldinBeijingyesterday.A、turnedup
Manyfamousscientists_______atthemeetingheldinBeijingyesterday.A、turnedu
Scientistsarebuildingtheworld’sfirstthinkingrobot.It’strue.Some
Scientistsarebuildingtheworld’sfirstthinkingrobot.It’strue.Some
Scientistsarebuildingtheworld’sfirstthinkingrobot.It’strue.Some
Manyfamousscientists________atthemeetingheldinBeijingyesterday.A、turned
Scientistsarebuildingtheworld’sfirstthinkingrobot.It’strue.Some
Thescientistswantedtokeeppeople______aboutthebreakthroughintheirexpe
Accordingtothepassage,scientistsusedtothinkthattheX-rayswereproduced
Accordingtothepassage,scientistsusedtothinkthattheX-rayswereproduced
随机试题
WhydidthecouplerecognizeRod’svoiceontheradioimmediately?[br][origin
【B1】[br]【B6】[originaltext]Eversincethebreakingofthe"ironbowl"inC
WhenofficialsinNewYorkCitybegantopiecetogetherhowSuperstormSandy
什么是法定再保险?我国加入WTO之前对法定分保的“入世”承诺是什么?
公路工程施工过程中,监理工程师对施工现场废气、污水、噪音等污染物排放进行控制,这
公路基本建设项目一般采用()设计。A.一阶段 B.两阶段 C.三阶段 D.
临产的标志有______。
根据《公益事业捐赠法》,()不能作为公益事业捐赠的受赠人。A.A市贫困大学生小
请为某企业设计一份绩效管理调查问卷。
M公司用甲材料生产A产品.甲材料标准价格是100元/千克,用量标准为5千克/件;
最新回复
(
0
)