Question

S maximum depolarization approaches, the sodium ion channels close. if you could experimentally prevent the ion channels from closing, what would be an expected response?

multiple choice
A. the potassium channels would remain open so all ions would continue to move across the membrane the resting membrane potential would not be reestablished.
B. the sodium ions would move through the potassium channels.
C. potassium ions would no longer diffuse across the membrane.

Answer 1

If sodium ion channels did not close, the resting membrane potential would not be reestablished due to continuous sodium inflow, disrupting the action potential process. The correct answer is option a.

Step-by-step explanation:

If sodium ion channels were experimentally prevented from closing, the expected response would be that the resting membrane potential would not be reestablished. Normally, during an action potential, the sodium ion channels and potassium ion channels open to facilitate depolarization and repolarization, respectively. Sodium channels closing and potassium channels remaining open are essential for returning the membrane to its resting state by allowing extracellular potassium to flow out, taking positive charge with it. If sodium channels remained open, sodium ions would continually enter the cell, preventing repolarization and maintaining the depolarized state.

The correct option in this scenario would be A: the potassium channels would remain open so all ions would continue to move across the membrane and the resting membrane potential would not be established. This malfunction would disrupt the nuanced balance necessary for the action potential and normal cell function, potentially leading to uncontrolled cell activity.