Arun
Last Activity: 7 Years ago
Dear student
The resting membrane potential arises due to the combined effects of three factors, which determine what ions move across the cell membrane in an unstimulated cell (at rest).
Ions are not evenly distributed between the inside and the outside of a cell. As we just learned, sodium is nearly 10 times more concentrated outside the cell than inside. Conversely, potassium is nearly 30 times more concentrated inside the cell than outside. The uneven distribution of ions leads to concentration gradients across the cell membrane. Given the opportunity, ions will move down their concentration gradient (i.e., from an area where they are highly concentrated to an area where they are less concentrated). So, given the chance, sodium ions would move into the cell and potassium ions would move out of the cell based on their respective concentration gradients.
Regards
Arun(askIITians forum expert)