The "undershoot" phase of hyperpolarisation is due to ________.
A) slow opening of voltage-gated sodium channels
B) sustained opening of voltage-gated potassium channels
C) rapid opening of voltage-gated calcium channels
D) slow restorative actions of the sodium-potassium ATPase

Question

Quizplus · Accepted Answer

The undershoot phase of hyperpolarization occurs after the peak of the action potential, and it is caused by the sustained opening of voltage-gated potassium channels. As these channels remain open, potassium ions continue to flow out of the cell, making the inside even more negative than the resting membrane potential. This undershoot phase is also known as afterhyperpolarization.

The "Undershoot" Phase of Hyperpolarisation Is Due to ________