Medical Term Definition

ATP

Adenosine triphosphate (ATP) is a molecule that stores and transfers readily usable energy within cells.

Cells use ATP to power many processes, including muscle contraction, active transport across cell membranes, chemical reactions, and the synthesis of cellular components. ATP can release usable energy when one of its phosphate groups is removed, producing ADP and inorganic phosphate.

Mitochondria produce much of the ATP used by human cells through cellular respiration, although ATP can also be produced by other cellular pathways.

QUICK FACT

ATP is often called the cell’s “energy currency,” but it is more accurate to think of it as a short-term energy-transfer molecule rather than a long-term energy store.

COMMONLY CONFUSED WITH

Glucose: Glucose is an important fuel molecule that can be broken down to help produce ATP; ATP is the immediate energy-transfer molecule used to power many cellular processes.

SEE ALSO