Comparison between Osmosis and Diffusion

By: Prof. Dr. Fazal Rehman Shamil | Last updated: February 3, 2024

Let me share with you a comparison between Osmosis and Diffusion.

Aspect              Osmosis        Diffusion
Introduction·        The movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.·        The movement of molecules from an area of higher concentration to an area of lower concentration, along a concentration gradient.
Medium·        Involves the movement of water (solvent) across a membrane.·        Can involve the movement of any type of molecule
Selective Barrier·        Requires a selectively permeable membrane that allows the passage of water molecules·        Can occur in the absence of a membrane
Dependence on medium·        Primarily occurs in aqueous solutions and relies on the presence of water molecules.·        Can occur in liquids, gases and across membranes, depending on the properties of the diffusing substance.
Role in Cells·        Crucial for maintaining cell turgor pressure and water balance in cells.·        Important for nutrient uptake, waste removal and the overall equilibrium of substances within cells.
Examples·        Water movement into plant cells and red blood cells.·        Perfume spreading in a room

·        Movement of oxygen and carbon dioxide in and out of cells during respiration.