Osmosis is a natural process that occurs in cells in order to maintain the balance between the intercellular medium and the extracellular medium, that is, osmosis aims to maintain cellular homeostasis.
This process is characterized by the movement of water in and out of the cell through the cell membrane. Osmosis occurs when the concentration of water inside the cell is out of balance with the concentration of water outside the cell, so the water passes through the membrane to balance these concentrations.
An action potential is defined as a sudden, fast, transitory, and propagating change of the resting membrane potential. Only neurons and muscle cells are capable of generating an action potential; that property is called the excitability.
