For potassium ions in a living cell, the electrical and concentration gradients pull in which directions?

1. Cells hold higher concentrations of potassium and lower concentrations of sodium than the extracellular fluid does. 2. Potassium is a positive ion and the cell interior is negative, so the electrical gradient tends to drive potassium into the cell. 3. Potassium is already more concentrated inside, so its concentration gradient tends to drive it out of the cell. 4. The two forces therefore oppose each other for potassium, which is what makes it more complex than sodium. 5. For sodium both forces point the same way, inward, because sodium is scarce inside and the interior is negative. 6. Any answer with both potassium forces pointing the same way describes sodium rather than potassium. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 5 "Structure and Function of Plasma Membranes", section 5.3 Active Transport_