Sodium-Potassium ATPase

An illustration of the action of the sodium-potassium ATPase. This transmembane protein uses energy captured from the breakdown of ATP to maintain the concentration gradients of sodium and potassium ions across the plasma membrane. For every ATP consumed, 3 sodium ions are pumped out of the cell, and 2 potassium ions pumped into the cell. Public domain image created by wikimedia commons user LadyofHats. http://en.wikipedia.org/wiki/File:Scheme_sodium-potassium_pump-en.svg