It's usually shown like a clock is shown here, where time 0, which is at the top here is right at the end of mitosis where you have two new cells that are formed.

通常会用一个类似时钟的图来图示,0时刻,在最上端 为上次有丝分裂终点,代表两个新细胞刚刚形成

耶鲁公开课 - 生物医学工程探索课程节选