If X is the number of cells, then the rate of change of X, dX/dt, the rate of change of the cell population, how fast division is taking is proportional to the number of cells I have.

如果X是细胞数目,那么X的改变率就是dX/dt,就是细胞数目的改变率,分裂的速度有多快,和细胞数量呈比例关系

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