In scientific lingo, the process of intermingling of molecules in various states of matter can occur by two methods ‘“ diffusion and osmosis. But, while diffusion is the intermingling of molecules as a result of their inherent kinetic energy based on random motion, whether in a gas, liquid or solid, osmosis is the flow of liquid between two sections separated by a semi-permeable or permeable membrane. Osmosis usually refers to the flow of water.
Osmosis, therefore, is a selective form of diffusion. Diffusion is based on random flow of molecules and is much more common in gases while, osmosis is based on the inherent solvent capacity of the molecules of a substance in water. It is the membrane, in osmosis, that allows the flow of certain types of molecules while restricting the flow of other types.
In both osmosis and diffusion, the molecules necessarily flow from an area of higher concentration to the lower one. A practical example of diffusion is when you spray a room freshener in a corner and the entire room soon becomes full with the scent. A practical example of osmosis is when you start feeling thirsty after eating something salty because the excess salt draws water to the cells in the body.
In scientific terms, both diffusion and osmosis are categorized as means of ‘passive transport’ as no external energy is required for the flow of molecules. Osmosis is an important biological concept.
Diffusion and osmosis both have an important role to play in living organisms for maintaining homeostasis ‘“ an internal balanced condition or equilibrium to regulate various mechanisms through cellular functioning.
Lately, osmosis has also been used as a poetic concept and to define an educational concept in which a child learns by watching, interacting and by merely being in the company of teachers and fellow students. Diffusion, however, has not received this ‘exalted status’ yet!
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