Question

the resting membrane potential is mainly determined by ________. answer options: the concentration gradient of k⁺ and the differential permeability of the plasma membrane to k⁺ and other ions; the concentration of na⁺; the concentration of cl⁻; the concentration of protein anions outside the cell; i dont know yet

Explanation:

The resting membrane potential (RMP) is mainly determined by the concentration gradient of \( K^+ \) and the differential permeability of the plasma membrane to \( K^+ \) and other ions. At rest, the cell membrane is more permeable to \( K^+ \) than to other ions like \( Na^+ \) or \( Cl^- \). \( K^+ \) moves out of the cell down its concentration gradient, creating a negative charge inside the cell. The concentration of \( Na^+ \) (second option) is more relevant for action potentials, not RMP. The concentration of \( Cl^- \) (third option) has a smaller role. Protein anions are mostly inside the cell, not outside (fourth option is incorrect). So the first option is correct.

Answer:

the concentration gradient of \( K^+ \) and the differential permeability of the plasma membrane to \( K^+ \) and other ions