"Reducing salt in the food supply needs to be a gradual process for a couple of reasons."

VOA: standard.2010.04.22

Several things happen during mitosis, first, when a cell enters the process of mitosis it already has twice the DNA that it needs.

有丝分裂中有几个重要的步骤,首先,当细胞进入有丝分裂过程,细胞中已含有两倍于其正常所需的DNA

耶鲁公开课 - 生物医学工程探索课程节选