Question

64 in cardiac muscle, after the plateau phase and at the beginning of repolarization, multiple choice voltage - gated sodium channels open. voltage - gated potassium channels open. voltage - gated calcium channels open.

Explanation:

In cardiac muscle, at the start of repolarization after the plateau phase, voltage - gated potassium channels open to allow potassium ions to exit the cell, leading to repolarization. Sodium channels are mostly inactivated and calcium channels close or are closing during this phase.

Answer:

B. voltage - gated potassium channels open