The absolute refractory period occurs because _______ channels cannot be opened, and the relative refractory period occurs because _______. A) voltage-gated Na⁺; voltage-gated K⁺ channels cannot be opened B) voltage-gated K⁺; voltage-gated Na⁺ channels remain open C) voltage-gated Na⁺; voltage-gated K⁺ channels remain open D) voltage-gated Na⁺; Na⁺-K⁺ pumps are activated

Question

Quizplus · Accepted Answer

The absolute refractory period occurs because voltage-gated Na⁺ channels are inactivated and cannot be opened. The relative refractory period occurs because voltage-gated K⁺ channels remain open, making it harder to reach the threshold for another action potential.

The Absolute Refractory Period Occurs Because _______ Channels Cannot Be