How the Cell Cycle Operates

A cell is a dynamic system. It is "born," lives, grows, reproduces, and dies. Each cell works like an automated factory, duplicating parts of it. It interacts with its environment, sending and receiving signals—electrical and chemical—to act on or cause action elsewhere, and guarding against invaders or aggressively attacking other cells. A cell changes shape, moves off to another place, and sometimes links up with other cells.