问题
单项选择题
关于立克次体的叙述，正确的是（）
A.比病毒更低级的微生物
B.生存不依赖细胞环境
C.无细胞壁结构
D.在细胞内生长和繁殖
E.只有RNA一种核酸
答案
参考答案：D
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关于立克次体的叙述，正确的是（）
A.比病毒更低级的微生物
B.生存不依赖细胞环境
C.无细胞壁结构
D.在细胞内生长和繁殖
E.只有RNA一种核酸
参考答案：D
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| Wild animals are important to us. They 1 together with us on the earth. If there are no 2 on the earth, we 3 will not live on. So we should take good care of them. But some people 4 don't know the importance of protecting them. They kill wild animals for 5 and other things. Every day many wild animals are killed. So lots of them have died out. We can't see 6 any more. Today wild animals are becoming fewer and 7 . If people don't protect them, they will die out. If this 8 , there will be no animals left on the earth. 9 , many children have begun to know the importance of protecting wild animals. They ask 10 to stop killing them. They also teach others about the importance of protecting them. Now many countries 11 some laws to protect them 12 stop people from killing them. Protecting wild animals is the 13 of each of us. We should do our best 14 them, because protecting them is protecting 15 . | ||||
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