By Janet Rae-Dupree, Pat DuPree

The cell life cycle, usually referred to simply as the cell cycle or the CDC (cell division cycle), extends from the beginning of one cell division to the beginning of the next division. The human body produces new cells every day to replace those that are damaged or worn out.

The cell cycle is divided into two distinct phases:

  • Interphase: Sometimes also called the resting stage, that label is a misnomer because the cell is actively growing and carrying out its normal metabolic functions as well as preparing for cell division.

  • Mitosis: The period of cell division that produces new cells.

New cells are produced for growth and to replace the billions of cells that stop functioning or are damaged beyond repair in the adult human body every day. Some cells, like blood and skin cells, are continually dividing because they have very short life cycles, sometimes only hours. Other cells, such as specialized muscle cells and certain nerve cells, may never divide at all.