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
23
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/3615813.html
相关试题推荐
[originaltext]Duringthepastdecade,therehasbeenamultifoldincreasei
[originaltext]Duringthepastdecade,therehasbeenamultifoldincreasei
[originaltext]ThelivingconditionsforthepoorandforimmigrantsinNew
[originaltext]ThelivingconditionsforthepoorandforimmigrantsinNew
[originaltext]ThelivingconditionsforthepoorandforimmigrantsinNew
[originaltext]M:DoyoumindifIaskyouhowoldyouare?W:Actually,I’drat
[originaltext]M:WhatisMr.JohnsongoingtodowithhisoldhouseonParisRo
[originaltext]M:WhatisMr.JohnsongoingtodowithhisoldhouseonParisRo
[originaltext]M:WhatisMr.JohnsongoingtodowithhisoldhouseonParisRo
[originaltext]M:WhatisMr.JohnsongoingtodowithhisoldhouseonParisRo
随机试题
PASSAGETHREE[br]Whereistheauthorfrom?Australia从文章第一段末句LikemanyAustralia
[originaltext]W:Hi,ProfessorHiggins.M:Hi,Julia.W:Wouldyoubeabletoh
TypesofMoneyThefunctionsofmoneyasamediumofexc
Cottonoutputwas______thanlastyear.A、20percenthighB、20percenthigherC、
Itdoesn’tcomeasasurprisetoyoutorealizethatitmakesnodifference
气割或机械剪切的零件,需要进行边缘加工时,其刨削量不应小于2.0mm。()
某企业由于财务印章被盗用,导致该企业在开户行的巨额存款在几天内被取走,给该行造成
国家鼓励教科书( )A.由国务院统一发行 B.循环使用 C.内容尽量丰富复杂
下列哪一证据规则属于调整证据证明力的规则? A.传闻证据规则 B
某新建建设项目生产单一产品,正常年份的设计生产能力为100万件,年固定成本为58
最新回复
(
0
)