Question

required information
why does depolarization occur?
multiple choice
more k+ diffuse into the cell than na+ diffuse out of it.
more k+ diffuse out of the cell than na+ diffuse into it.
more na+ diffuse into the cell than k+ diffuse out of it.
more na+ diffuse out of the cell than k+ diffuse into it.
both na+ and k+ diffuse into the cell.

Explanation:

Depolarization occurs when the membrane potential of a cell becomes less negative (more positive). This is due to the influx of positively - charged sodium ions ($Na^+$) into the cell. When more $Na^+$ diffuse into the cell than $K^+$ diffuse out of it, the inside of the cell becomes more positive relative to the outside, leading to depolarization.

Answer:

C. More $Na^+$ diffuse into the cell than $K^+$ diffuse out of it.