首页
登录
职称英语
[originaltext] Cultural controls are the oldest methods that have been used
[originaltext] Cultural controls are the oldest methods that have been used
游客
2024-04-25
28
管理
问题
Cultural controls are the oldest methods that have been used to manage pest populations. However, with the development of synthetic pesticides these controls were rapidly abandoned or de-emphasized and research on them was largely discontinued.(19)Today, we are going to talk about a natural way some plants respond to being invaded by pests. The plants react by emitting a chemical signal, which acts like a call for help. Let’s take corn plants for example. Sometimes,(20)a kind of insects that cannot fly chew on the corn leaves; when this damage happens, the plant releases a chemical scream that attracts a kind of bees. The bees respond to the signal by flying to the chewed on leave, and laying their eggs on the insects.(21)The insects die in the next few days as the bees’ offspring will eat the insects. Thus the corn plant prevents all its leaves from being eaten by the insects. This chemical scream is specific. It’s only released after the plant has damaged by the insects. A plant damaged in other ways does not give off the same signal, nor does undamaged plants. Cotton and probably many other plants use similar type of defense against pests.(22)By enhancing this natural response in plants, researchers might reduce, some day even eliminate the need for chemical pesticide, which can cause ecological damage. For example, scientists might breed plants for this screaming trait, or they might transplant specific genes to increase the release of the chemical signals.
19. What’s the main purpose of the talk?
20. What causes the corn plant to emit the chemical signal?
21. How do the bees protect the damaged corn plant?
22. What is the meaning of enhancing this natural response in plants?
选项
A、Insects chewing on its leaves.
B、Bees laying eggs on its leaves.
C、Pesticides sprayed on its leaves.
D、Knives cutting its stalk.
答案
A
解析
文章中提到,一种不会飞翔的昆虫会咀嚼玉米的叶子,当这种伤害出现时,植物就会释放一种化学信号吸引一种蜜蜂,故答案为A)。
转载请注明原文地址:https://tihaiku.com/zcyy/3570780.html
相关试题推荐
[originaltext]Culturalcontrolsaretheoldestmethodsthathavebeenused
[originaltext]Goodafternoon,everybody,todayIamgoingtotellyousome
[originaltext]M:So,you’veseenobviouslylifeinFrance,familylifeinFranc
[originaltext]M:So,you’veseenobviouslylifeinFrance,familylifeinFranc
[originaltext]M:So,you’veseenobviouslylifeinFrance,familylifeinFranc
[originaltext]M:Hey,Vale.Sinceyou’refromArgentina,I’dhavetoaskyouab
[originaltext]M:Hey,Vale.Sinceyou’refromArgentina,I’dhavetoaskyouab
[originaltext]W:Mywatchstoppedagain.AndIjustgotanewbattery.Thatmad
[originaltext]W:Mywatchstoppedagain.AndIjustgotanewbattery.Thatmad
[originaltext]W:Mywatchstoppedagain.AndIjustgotanewbattery.Thatmad
随机试题
Carelessnessmadehimfallinhisjob______.A、interviewB、intentionC、stomachD、
超高压输电线路防雷措施最普遍使用的是避雷器。
A. B. C. D.
理财产品风险评级结果应当以风险等级体现,由低到高至少包括()个等级,并可以
(2017年真题)关于为有关基金业务活动出具法律意见书的律师事务所,下列表述正确
证券公司申请介绍业务资格,对外担保及其他形式的或有负债之和不高于净资产的20%,
基础心理学是研究()。 (A)正常成人心理现象的心理学基础学科 (B
在仓库内将原材料加工组合成另一种产品的作业,体现了物流活动的( )。A.占用效用
一台变压器的高压绕组由两个完全相同可以串联也可以并联的绕组组成。当它们同绕向串联
某安装公司承包一商场的建筑电气施工。工程内容有变电所、供电干线、室内配线和电气照
最新回复
(
0
)