The Relative Concentrations of Na⁺ and K⁺ Remain Constant During

question 2

Multiple Choice

The relative concentrations of Na⁺ and K⁺ remain constant during a single action potential,despite movement of these ions across the membrane,because

• A)they cross back immediately through recovery channels.
• B)they are pumped back across using the Na⁺/K⁺ ATPase pump.
• C)they are forced back across the membrane as the action potential moves away.
• D)the refractory periods do not end until all ions have been returned to their original areas.