Most animal cell membrances have protein that pump ions out of the cell potassium ions into the cell

sodium.

Most cell membranes have a sodium-potassium pump. It is an enzyme that pumps sodium ions out of the cell and potassium ions into the cell. It moves 3 sodium ions out and 2 potassium ions in. Both ions are transported against the concentration gradient. Thus, the sodium-potassium pump provides one positive charge carrier to the extracellular space.

b brown mice / white sand dunes