首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
What conclusion can be drawn from the scientists’ observation?
What conclusion can be drawn from the scientists’ observation?
admin
2014-07-20
30
问题
What conclusion can be drawn from the scientists’ observation?
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、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 insects which survived from a certain kind of insecticide.
答案
A
解析
“Scientists have discovered that plants themselves produce 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 u-sing the
转载请注明原文地址:https://kaotiyun.com/show/PyTK777K
0
专业英语四级
相关试题推荐
Peoplethinkingabouttheoriginoflanguageforthefirsttimeusuallyarriveattheconclusionthatitdeveloped(1)_____asa
Peoplethinkingabouttheoriginoflanguageforthefirsttimeusuallyarriveattheconclusionthatitdeveloped(1)_____asa
Peoplethinkingabouttheoriginoflanguageforthefirsttimeusuallyarriveattheconclusionthatitdeveloped(1)_____asa
Peoplethinkingabouttheoriginoflanguageforthefirsttimeusuallyarriveattheconclusionthatitdeveloped(1)_____asa
Sixoutoftenprisonersinchainsareblack,whichis______thechaingangscallupimagesofslaveryincenturiesgoneby.
Almost60%offive-year-oldsinsomeofBritain’spoorestareasdonotreacha"goodlevel"ofbehaviourandunderstanding—doubl
StrikesanddemonstrationsinGermany,BritainandFrancehelpedtomaketheshorterworkingweekaunionpriority.Employersga
Everyyearthousandsofpeoplearearrestedandtakentocourtforshop-lifting.InBritainalone,aboutHK$3,000,000’swortho
随机试题
西汉时开通了历史上著名的丝绸之路。()
提出“寓教于乐”的是【】
A.虹膜B.脉络膜C.巩膜D.角膜E.睫状体构成纤维膜后部的是()
葡萄胎清宫术前准备物品中哪项不需要
x企业资产总额为6000万元,以银行存款500万元偿还借款,并以银行存款500万元购买固定资产后,该企业资产总额为()万元。
2019年5月20日,甲公司以银行存款200万元(其中包含乙公司已宣告但尚未发放的现金股利5万元)从二级市场购入乙公司100万股普通股股票,另支付相关交易费用1万元,甲公司将其划分为以公允价值计量且其变动计入当期损益的金融资产。2019年12月31日,该股
紧追权,是指沿海国拥有的由本国的军舰、军用飞机或得到正式授权且有清楚可识别标志的政府船舶或飞机对违反该国法规并从该国管辖范围内的海域向公海行驶的外国船舶,在视听分外内发出停止信号后开始进行连续不断且可以持续至公海,但不能是第三国或被追船舶本国海域的紧追的权
提供计算机网络服务的是网络服务供应商(ISP),它包括()。
当前微机上运行的Windows属于()。
Thereareplentyofso-calledenergydrinksonthemarket.Mostofthemhaveanattractivecolorandcoolname.Butafteracare
最新回复
(
0
)