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
84
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:https://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
他努力控制住自己的感情,假装没有听见那个令人悲痛的消息。Hetriedtocontrolhimself,pretendingnottohear
A—BandwidthB—BBS(BulletinBoardSystem)C—Browser
Focusonwhatyoudobest.Thisage-oldstrategyhasworkedwellforRealNe
Blueistheworld’sfavoritecolor.Itisalsothecolormostoften【S1】_____
国家通用语言文字的基本原则包括①家推广普通话,推行规范汉字②公民有学习和使用国家
在淋巴细胞转化实验中,不属于非特异性刺激物的是A.PHA B.ConA C.
女性,32岁。门诊就诊,2个月来干咳、胸闷憋气,心悸,呼吸困难,夜间发作明显,影
对急性牙髓炎晚期止痛的应急处理,最有效的方法是A.封闭疗法 B.针刺止痛 C
远期交易的特征是()。A.即时交收或交割 B.履约回旋余地大 C.存在
肝硬化最危重的并发症是A.肝性脑病 B.原发性肝癌 C.肝肾综合征 D.自
最新回复
(
0
)