Question

How does the sodium-potassium ion pump maintain the membrane potential?A. It pumps 3 Na+ ions into the cell for every 2 K+ ions it pumps out of the cell.B. It pumps 3 Na+ ions out of the cell for every 2 K+ ions it pumps into the cell.C. It pumps 2 Na+ ions into the cell for every 3 K ions it pumps out of the cell..D. It pumps 2 Na+ ions out of the cell for every 3 K ions it pumps into the cell.

Answer 1

The ion-potassium pump is maintained by the sodium–potassium adenosine triphosphatase, an enzyme that can be found in the membrane of animal cells and uses ATP to change Na+ (sodium) and K+ (potassium) concentrations inside and outside the cell. In its process, the enzyme pumps three Na+ ions from the inside to the outside of the cell, and also pumps two K+ from the outside to the inside of the cell. Therefore, the correct answer is B. It pumps 3 Na+ ions out of the cell for every 2 K+ ions it pumps into the cell.