试题与答案

科学家做过如下实验,将深色桦尺蛾和浅色桦尺蛾分别进行标记,然后放养于不同的地点,

题型:读图填空题

题目:

科学家做过如下实验,将深色桦尺蛾和浅色桦尺蛾分别进行标记,然后放养于不同的地点,一段时间后,将所释放的桦尺蛾尽量收回,统计其数目,结果如下表:

类型数据

项目

工业污染区非工业区
深色蛾浅色蛾深色蛾浅色蛾
释放数目154只164只472只496只
再回收率58﹪25﹪6﹪42﹪
(1)桦尺蛾的体色有深浅之分,这是一种          现象(“遗传”或“变异”)。假设深色由显性基因控制(用B表示),浅色由隐性基因控制(用b表示),那么深色蛾的基因组成可能是

                         

(2)从表中可以看出,在不同环境中生活着的桦尺蛾,保护色是不同的。根据达尔文理论,保护色的形成是                的结果。

(3)桦尺蛾的个体发育要经过卵、幼虫、          、成虫四个阶段,叫完全变态发育。

(4)桦尺蛾的幼虫对桦树的危害很大。用            方法控制这种林业害虫,既经济又环保。

答案:

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参考答案:D解析:本题考查电信市场的内容。《电信条例》规定国家对电信市场采取经营许可的市场准入管理制度。取得经营许可证后可以合法进入电信业务市场,参与电信业务市场的公平竞争,经营许可证是进入电信业务...

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