问题 选择题

在如图所示的食物网中,要使E的产量最高,把能量集中引向E的食物链应是(    )。

A.A→B→C→E

B.A→B→E

C.A→D

D.A→B→C

答案

答案:B

题目分析:生态系统中的能量流动的特点是:单向流动,逐级递减,由于生物自身的呼吸消耗,以及植物的残枝落叶和动物的骨骼、皮毛等难以被下一个营养级的生物利用,造成了能量在沿着食物链流动的过程中是逐级递减的,一般地说,再输入到下一个营养级的能量中,只有10%~20%的能量能够流入下一个营养级,在一个生态系统中,营养级越多,在能量流动中消耗的能量就越多,所以要使E的产量最高,把能量集中引向E的食物链应是最短的那条食物链,即A→B→E,故选B。

阅读理解

阅读理解。

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