500
Describe the entire Sodium-Potassium pump process.
1) 2 Na+ fit into the 2 slots in the carrier protein
2) A phosphorous molecule detaches from ATP (->ADP) and attaches to the protein, giving it energy to change its shape.
3) the 2 Na+ float out of the cell against their concentration gradient, allowing 3 K+ ions to fit into their 3 slots in the protein.
4) The phosphorous molecule detaches from the protein, allowing the protein to relax and revert back to its original shape.
5) The 3 K+ ions float out against their concentration gradient into the cell, allowing the cycle to repeat.