Also known as the sodium/potassium pump, the Na+/K+ pump is the most common primary active transport mechanism in human cells. It helps maintain the electrochemical gradient in cells. Although Na+ and K+ ions have equal charge, the pump expells 3 Na+ ions for each 2 K+ ions that it takes in. This reaction requires energy from the breakdown of adenosine triphosphate (ATP). 40% (if I remember correctly) of a cell's energy is used for these pumps. They are especially prevalent in nerve and muscular cells due to their method of transmission of impulses, both action potentials and graded potentials.

Log in or register to write something here or to contact authors.