Sodium-Potassium Pump Cycle:

a. 3 Na+ and a phosphate functional group from ATP bind to the pump
b. The pump changes shape, transporting the 3 Na+ across the cell membrane
c. 2 K+ bind to the pump and are transported into the cell
d. The phosphate group and 2 K+ molecules are released by the cell, where the phosphate group joins ADP to form ATP and the cycle starts over again
Maintain [ ] gradient required to function