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问题 选择题

细胞通过分裂产生新细胞，下列关于细胞分裂的叙述不正确的一项是（　　）

A．细胞分裂时，先是细胞核由一个分成两个，随后细胞质分成两份，每份含一个细胞核

B．细胞分裂时，植物细胞会在原来的细胞中央形成新的细胞膜和新的细胞壁

C．细胞分裂时，染色体会进行复制，新细胞和原细胞的染色体形态相同，但是数目加倍

D．细胞分裂时，染色体会进行复制，形成的两个新细胞的染色体形态和数目相同

答案

A、细胞分裂时，先是细胞核由一个分成两个，随后细胞质分成两份，每份含一个细胞核，A正确；

B、细胞分裂时，植物细胞会在原来的细胞中央形成新的细胞膜和新的细胞壁，B正确；

C、细胞分裂时，染色体会进行复制，随着分裂的进行，染色体分成形态和数目相同的两份，分别进入两个新细胞中．因此新细胞和原细胞的染色体形态相同，数目相同，C不正确；

D、细胞分裂时，染色体会进行复制，形成的两个新细胞的染色体形态和数目相同，D正确．

故选：C．

单项选择题

（）在西方教育史上第一次将教育分为体育、德育、智育三部分，并作了详细论述。

A.《教育漫话》

B.《爱弥儿》

C.《民主主义与教育》

D.《学校和社会》
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填空题

根据课文内容填空,每空一词.

     But how could the _1_____ believe it was natural? Everywhere they looked nearly everything was

___2___. All of the city's hospitals, 75% of its factories and buildings and 90% of its homes were

___3___. ___4___ covered the ground like red autumn leaves. No wind, however, could blow them

away. Two dams fell and most of the bridges also fell or were not safe for travelling. The railway

___5___ were now useless pieces of steel. Tens of thousands of cows would never give milk again.

Half a million pigs and millions of chickens were dead. Sand now filled the wells instead of water.

People were ___6___. Then, later that afternoon, another big ___7___ which was almost as strong

as the first one shook Tangshan. Some of the rescue workers and doctors were ___8___ under the

ruins. More buildings fell down. Water, food, and ___9___ were hard to get. People began to wonder

how long the ___10___ would last.
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