Question

16 what occurs during depolarization of an axon? multiple choice sodium channels open and sodium diffuses into the cell potassium channels open and potassium diffuses into the cell. sodium channels open and sodium diffuses out of the cell. potassium channels open and potassium diffuses out of the cell.

Explanation:

During depolarization of an axon, sodium channels open. Sodium ions (\(Na^+\)) have a higher concentration outside the neuron compared to inside. Due to this concentration gradient, sodium diffuses into the cell. This influx of positive - charged sodium ions changes the membrane potential from a negative resting potential towards a more positive value.
Potassium channels opening and potassium diffusing in or out is more relevant to repolarization (potassium diffusing out) or other stages (potassium diffusing in is not a typical event in the standard action - potential related to axon depolarization). Sodium diffusing out would not cause depolarization as it would not make the inside of the cell more positive.

Answer:

Sodium channels open and sodium diffuses into the cell.