9781422276129

Cell Division Cells divide every day, every hour, and every second of our lives. The process of cell division is called mitosis. When a cell divides, it produces cyclins, proteins that helps cells in mitosis. Cells follow a routine regarding when to take food in, when to divide, and when to stop working or die. The process of the programmed death of cells is called apoptosis. This pattern is known as the “cell cycle.”

SIDEBAR: DID YOU KNOW?

• An adult human being has more than 37 trillion cells. • In addition to biology, the scientist Robert Hooke did important in many other fields, including astronomy, geometry, and physics.

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