Types of Diffusion

Facilitated diffusion is the process of spontaneous passive transport of molecules or ions across a cell's membrane via specific transmembrane integral proteins.

Osmosis is the result of diffusion across a semipermeable membrane. If two solutions of different concentration are separated by a semipermeable membrane, then the solvent will tend to diffuse across the membrane from the less concentrated to the more concentrated solution.

Osmotic pressure is a colligative property, meaning that the osmotic pressure depends on the molar concentration of the solute but not on its identity. Osmosis is a vital process in biological systems, as biological membranes are semipermeable.

Passive diffusion occurs along a concentration gradient from high concentration to low concentration. At the end, net movement of solute ceases, when the concentrations are similar everywhere. However, in the case of active transport the movement is happening against the concentration gradient from low concentration to high concentration.