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sodium-potassium pump

sodium-potassium pump
Sodium-potassium pump
Image credit: Columbia University

A mechanism of active transport that moves potassium ions into and sodium ions out of a cell along a protein (or enzyme) channel. It is found in all human cells, but is especially important in nerve and muscle cells.

The sodium-potassium pump uses active transport, with energy supplied by ATP (adenosine triphosphate) molecules, to move 3 sodium ions to the outside of the cell for each 2 potassium ions that it moves in. One third of the body's energy expenditure is used in this process.

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