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
2024-06-02
32
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、Because farmers use less insecticides now.
B、Because farmers have been using insecticides for many years.
C、Because insects use the mechanisms against plants to fight insecticides.
D、Because insects have been eating plants for many million years.
答案
D
解析
昆虫吃植物的历史已经长达两亿五千万年“In fact, insects have been eating plants for as many as 250 million years”,所以它们的抗杀虫剂性能增长得非常迅速。因为它们已经习惯不断进化,对抗各种植物杀虫剂、人工杀虫剂:Now insects are using these same mechanisms to deal with man-made poisons—insecticides...insecticides has develop
转载请注明原文地址:http://tihaiku.com/zcyy/3615814.html
相关试题推荐
[originaltext]Theworld’sfirstcompletelyautomaticrailwayhasbeenbuilt
[originaltext]Theworld’sfirstcompletelyautomaticrailwayhasbeenbuilt
[originaltext]Afableisashortstorywhichisnottrue.Itisastorytha
[originaltext]M:Hey!Jenny,doyouwanttolivealongerlife?W:Why?Ofcour
[originaltext]W:Hi,Mark!How’sitgoing?M:Well,notsogreat.W:What’swro
[originaltext]M:Hello.W:Hello,Sam.ThisisPaulaHanson.Sorrytobotheryo
[originaltext]M:Hello.W:Hello,Sam.ThisisPaulaHanson.Sorrytobotheryo
[originaltext]M:Hello.W:Hello,Sam.ThisisPaulaHanson.Sorrytobotheryo
[originaltext]M:Hello.W:Hello,Sam.ThisisPaulaHanson.Sorrytobotheryo
[originaltext]W:Hi,Bob.IheardaboutyouraccidentbutIdidn’tthinkitwou
随机试题
Forthispart,youareallowed30minutestowriteanessaycommentingonthe
MoreattentionwaspaidtothequalityofproductioninFranceatthetimeo
[originaltext]M:Doyouwantyourtelevisionrepaired?W:Yes,butnotbythep
[originaltext]Goodmorning,class.Ihavesomegreatnewsforyouall.Cont
Whydoesthewomansaythemanhasledadangerouslife?[originaltext]W:Tony,y
罗尔斯的社会正义论和麦金泰尔的共同体主义被称为“新科技时代的伦理”或一种超越了传
自身免疫性溶血性贫血属于哪种超敏反应性疾病A.I型超敏反应B.Ⅱ型超敏反应C.Ⅲ
(2020年真题)焊接作业时,焊工遵循的作业文件有()。A.焊接作业指导书
二衬施工质量控制中,下列表述正确的有()。A、结构变形基本稳定的条件下施作
下列属于信息偏倚的是A.现患病例-新发病例偏倚 B.回忆偏倚 C.检出征候偏
最新回复
(
0
)