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
31
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
WhenIwasachild,myfamilyusedtogoonholidayeveryyeartovisitour
[originaltext]PresentlyIgotupanddressed,stuckmyviolinundermyjack
Theplaceofthechildinsocietyhasvariedforthousandsofyearsandhas
[originaltext]W:(19)Sorry,I’mlate.Thetrainwasdelayed.Igotstuckonthe
Childrenmodelthemselveslargelyontheirparents.Theydoso【C1】______thro
以下建筑常用的天然石材中,耐用年限较短的是( )。A.花岗石 B.石灰岩
吴女士,50岁,25年吸烟史,本人无糖尿病,血压150/90mmHg,体重指数2
请根据提供的营养调查信息设计普通人的运动方案 调查信息:白女士,40岁,全职太
A.发现药品质量问题 B.药品上市前风险评估 C.药品上市后风险评估 D.
参与B细胞活化的CD分子是A.CD3 B.CD4 C.CD40 D.CD8
最新回复
(
0
)