This lets me have a way of representing things that could be arbitrary in size. And some of these things could be huge, if they're themselves lists.

有些可能很大，如,果他们本身就是列表,那问题来了。

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The size of the cells could be different; maybe mitosis is asymmetrical in some way so that one of the cells ends up being bigger than the other.

细胞大小可能会不同,也许有丝分裂的过程是不对称的,致使子细胞一个大一个小

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