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若连续分裂的细胞处于一个细胞周期中，则细胞内（）
A、处于分裂期时会大量利用T与U
B、DNA复制和转录过程的每个起点都多次起始
C、染色体的数目与DNA分子的数目始终保持相同
D、严格的调控机制保证了细胞周期的有序运行

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There are many commonly held beliefs about eye glasses and eyesight that are not proven facts. For instance, some people believe that wearing glasses too soon weakens the eyes. But there is no evidence to show that the structure of eyes is changed by wearing glasses at a young age. Wearing the wrong glasses, however, can prove harmful. Studies show that for adults there is no danger, but children can develop loss of vision if they have glasses inappropriate for their eyes.
We have all heard some of the common myths about how eyesight gets bad. Most people believe that reading in dim light causes poor eyesight, but that is untrue. Too little light makes the eyes work harder, so they do get tired and strained. Eyestrain also results from reading a lot, reading in bed, and watching too much television. However, although eyestrain may cause some pain or headaches, it does not permanently damage eyesight.
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