Which of the following is responsible for the falling (repolarizing)phase of the action potential? A)Voltage-gated Na⁺ channels are opened B)The Na⁺, K⁺ pump restores the ions to their original locations inside and outside of the cell C)The permeability to Na⁺ increases greatly D)ATPase destroys the energy supply that was maintaining the action potential at its peak E)The permeability to K⁺ increases greatly while that to Na⁺ decreases

Question

Quizplus · Accepted Answer

During the falling (repolarizing) phase of the action potential, the permeability to K⁺ increases greatly while that to Na⁺ decreases. This allows K+ ions to leave the cell, which leads to repolarization or a return to the resting membrane potential. Therefore, choice E is the best answer.

Which of the Following Is Responsible for the Falling (Repolarizing)phase