plzzz give the explanation of the prosess of osmosis....... i know the definition of osmosis but i have no idea about the prossess of osmosis or how it takes place.......... plzzzzzz help as i had this in my exams but the explanation is not clear in my text book..

Osmosis is the movement of water molecules in a solution from a region of lower solute concentration to higher through a semi permeable membrane to equalize the concentration of both the solutions in contact.

When two solutions of different concentrations are placed by separating them with a semi permeable membrane, water from less concentrated (hypotonic) solution will cross the membrane and enters into the hypertonic solution (more concentrated). This is osmosis. This movement of water molecules will continue till both the solutions reach to an equal concentration (isotonic).

For example, when a dry raisin is placed inside pure water for some time, it will swell up as water enters inside the apricot raisin. It occurs due to osmosis. Here the concentration of solute is lower in water than inside the raisin. Thus water enters inside to maintain equilibrium.