首页
登录
职称英语
What conclusion can be drawn from the scientists’ observation? [br] [originalte
What conclusion can be drawn from the scientists’ observation? [br] [originalte
游客
2024-09-28
1
管理
问题
What conclusion can be drawn from the scientists’ observation? [br]
Scientists have discovered that plants themselves pro-duce many poisonous chemicals for defense against insects. But insects have developed ways of dealing with them and, in fact, have been eating plants for about 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 that farmers use less insecticides. At the moment, farmers 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, 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 at-tract 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.
Scientist hope that these and other measures will post-pone the day when farmers and scientists will have to stand by while new super-bugs which may be resistant to all poi-sons invade our farms and devour our crops.
选项
A、Farmers should use less insecticides.
B、Farmers should use a combination of two or three insecticides at once.
C、At certain times of the year, farmers should actually try to attract new insects onto the crops they are trying to protect.
D、Farmers should regularly spray crops as a precaution against problems that are caused by large numbers of pests.
答案
D
解析
“They should,instead,spray only where pests have actually been seen.”,“Secondly,farmers could use a combination of two or three insecticides at once.”,“farmers should actually try to attract insects onto the crops they are trying to protect”选项A,B,C在课文中都有提
转载请注明原文地址:https://tihaiku.com/zcyy/3778247.html
相关试题推荐
Thethreesuicidebombingsoccurredin______.[br][originaltext]Itgoesag
WherewillIraqiPrimeMinisterdeliveraspeechonTuesday?[originaltext]I
Whichofthefollowingistrueaboutthenewsitem?[originaltext]Theauthor
Wherecanpeopletakeadulteducationcourses?[br][originaltext]Millions
Wherecanpeopletakeadulteducationcourses?[br][originaltext]Millions
WhatiscommontoallthefilmsproducedinHollywood?[br][originaltext]
WhatiscommontoallthefilmsproducedinHollywood?[br][originaltext]
Themanislookingfor______[originaltext]M:Excuseme,Iwonderifyoucouldt
Whattopicarethemanandwomandiscussing?[originaltext]M:Ireallyappreciat
Thenewsitemmainlyabout[br][originaltext][29]Manyorganizationsarou
随机试题
Choosethecorrectletter,A,BorC.OnlineExchangeBusiness[br]Whichcountr
[originaltext]Centuriesago,duringtheMiddleAges,mostofthelandinEu
In1915EinsteinmadeatriptoGottingentogivesomelecturesattheinvit
微型计算机系统中,显示器属于表现媒体,鼠标属于()A.感觉媒体 B.传输
下列罪名中,个人不能构成犯罪主体的是()A.背信运用受托财产罪 B.违规
男,36岁。平素性格内向,近日情志不遂,精神抑郁,情绪不宁,善太息,胸胁胀痛,痛
患者,男性,38岁。车祸伤及头部,当即出现右侧鼻唇沟变浅,右外耳道流出淡血性液体
病员35岁,男,溃疡病出血,贫血貌,MCV85fl,MCH28pg,MCHC32
教学内容的表现形式有()。A.教学大纲 B.专业知识 C.课程 D.教材
从高炉安全生产的需要出发,富氧量是有限的,目前我国国内基本明确将富氧量控制在(
最新回复
(
0
)