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以下是引用lemontree在2003-3-15 16:46:00的发言：
Caterpillars of all species produce an identical hermone called"j h" that maitains 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 j h. 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, supports the view it would not be advisable to eradicate argricultural pests go through a caterpillars stage by spraying cropland with the enzyme mentioned above.
答案： any argricultural pest do not go through a caterpillars stage.
any argriculturally benificial insects go through a caterpillars stage
问题是：哪一项支持：用文中提到的“酶”消灭农业害虫的方法并不可取？
The key to the question is : "any argriculturally benificial insects go through a caterpillars stage "==任一种农业益虫都经过幼虫阶段。
Good luck!
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发表于 2003-3-15 16:46:00
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