题干

关于生态系统组成成分的描述,正确的是(  )

A:生态系统由生产者、消费者、分解者组成

B:动物属于消费者,原因是它不能自己制造有机物,直接或间接地以植物为食

C:细菌和真菌能够分解动植物尸体中的无机物,因此,属于分解者

D:阳光、空气和水与生态系统有密切的关系,但不属于生态系统组成成分

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答案(点此获取答案解析)

B

同类题3

完形填空

    In the middle of a beautiful day, I was feeling lost, as if the world was crashing on me. didn't know which way to go, except to head out to the countryside. I went to the spot where I used to take my kids-when I still had kids. Now they had  1and were leaving.

I was sitting alone in my car when I saw a man in his seventies, whose problem appeared bigger than mine. He stood near the edge of the road,2a kite spindle(风筝线锭) in his hands. Apparently, lost in thought, he stared skyward. I 3my neck to see how successful he had been in 4 the clouds. Following his string with my eyes, I almost lost5 of the other end. Finally, the kite rested on what seemed to be the highest branch of the 6tree in the park.  Obviously,  that was his grandson's kite!  The kite was a replica (复制品) of a beautiful bald eagle, and its wings spread 70pen. Grandpa had only one 8to his problem: cut the string.

"You wanted it to fly as high as it could. Bill. didn't you?" "Yes, Grandpa,9 wanted to keep it forever. " "There just comes a time when the only thing you can do is to cut the string and let it go. Perhaps by doing that, when it flies very high like real eagles do, it will come back to us. " Grandpa said.

    I 10 how the old man cut the string to let fly the kite. As the two walked away, looked to the 11. There I saw my answer, too. Today I have to cut the final strings that kept my two boys 12my reach. Though I want to keep them forever, I have taught them to fly like an eagle. Maybe by doing this, when it's time to soar like real eagles do. one day they would come back to me.