ChaseDream
搜索
返回列表 发新帖
00:00:00

Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding behavior. Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme halt the production of juvenile hormone. This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

Which of the following, if true, most strongly supports the view that it would NOT be advisable to try to eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

正确答案: C

更多相关帖子

524

帖子

15

好友

4712

积分

ChaseDream

注册时间
2003-03-17
精华
8
解析
查看: 1662|回复: 0
打印 上一主题 下一主题

OG-134

[复制链接]
楼主
发表于 2005-11-7 16:23:00 | 只看该作者

OG-134

134. Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding
behavior. Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme
halt the production of juvenile hormone. This enzyme can be synthesized and will, on being ingested by
immature caterpillars, kill them by stopping them from feeding.
Which of the following, if true, most strongly supports the view that it would not be advisable to try to
eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme
mentioned above?
(A) Most species of caterpillar are subject to some natural predation.
(B) Many agricultural pests do not go through a caterpillar stage.
(C) Many agriculturally beneficial insects go through a caterpillar stage.
(D) Since caterpillars of different species emerge at different times, several sprayings would be necessary.
(E) Although the enzyme has been synthesized in the laboratory, no large-scale production facilities exist as
yet.


为什么B不对呢?



刚刚发现已经有人讨论了  麻烦斑竹删掉我的贴吧:)  


重复发贴占用空间太不好意思了!


[此贴子已经被作者于2005-11-7 16:27:31编辑过]
您需要登录后才可以回帖 登录 | 立即注册

Mark一下! 看一下! 顶楼主! 感谢分享! 快速回复:

手机版|ChaseDream|GMT+8, 2024-11-27 05:00
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号

ChaseDream 论坛

© 2003-2023 ChaseDream.com. All Rights Reserved.

返回顶部