Describe process in the human body in which there is evidence of the cell cycle at work

I suspect this question should read "How long does a red blood cell live." A red blood cell lives for between 100 and 120 days. It takes 7 days for a new red blood cell to develop from stem cells. Stem cells are similar to base cells. They can also be seen as a general template from which specialized cells are made. Stem cells can be taken from a newborn baby's umbilical chord or extracted from an adult blood donor's blood.This