Metabolism is the sum of all of the chemical reactions within cells that release energy.

Metabolism

The set of life-sustaining chemical reactions in organisms, involving the conversion of food into energy, the creation of building blocks for proteins, lipids, nucleic acids, and some carbohydrates, and the elimination of metabolic wastes.

Chemical Reactions

Processes in which substances interact to form new products, involving the rearrangement of atoms or the transfer of electrons.

Energy Release

The process of making energy available for use by the body, typically through the breakdown of nutrients in cells to produce ATP, the energy currency of the cell.