首页
登录
职称英语
[originaltext] (32)Scientists have discovered that plants themselves produce
[originaltext] (32)Scientists have discovered that plants themselves produce
游客
2023-09-09
50
管理
问题
(32)Scientists have discovered that plants themselves produce many poisonous chemicals for defense against insects. But insects have developed ways of dealing with them. Guess how many years have the insects been eating plants. The number itself will scare you. (33) In fact, insects have been eating plants for as many as 250 million years. Now insects are using these same mechanisms to deal with man-made poisons—insecticides. This is why resistance of insects to insecticides has developed so rapidly.
What should be done? Scientists studying the problem suggest (34) that farmers use less insecticides. At the moment, farmers (34)regularly spray crops as a precaution against problems that are caused by large numbers of pests. They should, instead, spray only where pests have actually been seen. Secondly, (34)farmers could use a combination of two or three insecticides at once. To survive, the insects would need to become resistant to two or more insecticides at the same time.
The most surprising suggestion, perhaps, is that at certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect. The new insects will mate with those which survived from a certain kind of insecticide and will lessen the latter’s resistance to it.
(35) Scientists hope that these and other measures will postpone the day when farmers and scientists will have to stand by while new super-bugs which may be resistant to all poisons invade our farms and devour our crops.
选项
A、Insects have developed some sort of resistance to man-made poisons.
B、Insects have been eating plants for about 250 million years.
C、Farmers sometimes use a combination of two or three insecticides at once.
D、New insects mate with insecticide-surviving insects.
答案
A
解析
昆虫通过进化可以抵制植物本身的抗虫物质一一有毒化学物质poisonous chemicals,昆虫也可以通过相同的方式对付人工杀虫剂man-made poisons—insecticides。这就是昆虫的抗杀虫剂性迅速增强的原因。可见科学家发现了昆虫的抗杀虫剂性。故正确答案为A。
转载请注明原文地址:http://tihaiku.com/zcyy/2999547.html
相关试题推荐
[originaltext]M:HowdidSallygowithherpresentationlastnight?W:Nosoone
[originaltext]M:HowdidSallygowithherpresentationlastnight?W:Nosoone
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]Sciencefictionwritershaveoftenimaginedhumanbeingsgoin
[originaltext]It’sgenerallyagreedthatserious,violentcrimehasreached
[originaltext]M:Excuseme,areyouwaitingtobuyconcerttickets?W:Yes,Ia
[originaltext]M:Excuseme,areyouwaitingtobuyconcerttickets?W:Yes,Ia
[originaltext]M:Excuseme,areyouwaitingtobuyconcerttickets?W:Yes,Ia
[originaltext]M:Excuseme,areyouwaitingtobuyconcerttickets?W:Yes,Ia
[originaltext]M:Hey,Sally!Areyougoingtostayinthatbathroomfortheres
随机试题
Nowadays,somethinghasgoneterriblywrongwithouronce-proudAmericanway
AccordingtoMrs.Hammer,whenisthephoneinterviewlikelytotakeplace?[br]
Thefirstparagraphmainlyindicatesthat______.[br]Theauthor’sattitudeto
说明:假设你是学生会主席Johnson,请按以下提示写一则通知。时间:12月17日。内容:1.为庆祝元旦,拟于12月31日举办元旦晚会;2.每个系选送3
某高校拟借助银行一卡通项目资金建设学校无线网络,网络中心张主任带队调研,获得信息
根据巴甫洛夫的两种信号系统学说,“望梅止渴”是第二信号系统的活动。( )
不符合WHO对社区康复工作要求的内容是A.社区康复是在社区水平的康复 B.病伤
()保护应优先采用光纤通道。(A)纵联(B)母线(C)线路(D)
破窗现象:一个房子如果窗户破了,没有人去修补,隔不久,其它的窗户也会莫名其妙地
因对微博的无知,某局长和某主任在微博上泄露个人隐私,暴露其不道德的行为,受到有关
最新回复
(
0
)