試題詳解

34. How does the sodium-potassium pump contribute to the negative charge inside a cell?
(A) by expelling more sodium ions than potassium ions it brings in
(B) by absorbing more sodium ions than potassium ions it expels
(C) by maintaining an equal balance of sodium and potassium ions
(D) by converting sodium ions into potassium ions inside the cell
(E) by moving anions in and out of the cell in addition to cations