One of the interesting properties of cells that are in exponential growth is that the time to increase the cell number by a factor of 2 is always the same.

细胞有一个有趣的性质,那就是在指数增长阶段,细胞增长的速度,永远是以二为底数来增长的

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Because we underestimate the growth of exponential function.

因为我们低估了指数函数的增长。

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