Depolarization outcome description?

Depolarization outcome description?

• A. The interior becomes more negative
• B. The interior becomes more positive
• C. The interior remains at baseline
• D. The interior becomes more positive due to influx of cations

Answer: (D)

Depolarization means the inside of the cell becomes less negative as positive ions flow into the cell. This happens when voltage-gated Na+ channels open and Na+ rushes in, bringing positive charge inside and driving the membrane potential toward zero and beyond. So the interior becomes more positive due to influx of cations, which is the hallmark of depolarization. If the interior were to become more negative, that would be hyperpolarization; staying at baseline would mean no depolarization.

Depolarization means the inside of the cell becomes less negative as positive ions flow into the cell. This happens when voltage-gated Na+ channels open and Na+ rushes in, bringing positive charge inside and driving the membrane potential toward zero and beyond. So the interior becomes more positive due to influx of cations, which is the hallmark of depolarization. If the interior were to become more negative, that would be hyperpolarization; staying at baseline would mean no depolarization.