Question

How does the voltage sensitivity of K⁺ conductance contribute to the action potential?

Answer 1

^1.        Potassium channels role to ways potassium ions down their electrochemical gradient, doing so both rapidly (up to the diffusion rate of K⁺ ions in bulk water) and selectively (excluding, most notably, sodium despite the sub-angstrom difference in ionic radius).

2.      Naturally, these channels performance to set or reset the resting potential in many cells.

3.      In excitable cells, such as neurons, the delayed counter flow of potassium ions shapes the action potential.

4.      By causative to the regulation of the action potential duration in cardiac muscle, failure of potassium channels may cause life-threatening arrhythmias.

5.      Potassium channels may also be involved in maintaining vascular tone.

Main point

(1) Selectively permeable of the potassium K+ channels that are only open throughout the depolarization (2) Gentle potassium K+ channel activation or deactivation