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Diffusion is the process by which substances move down a concentration gradient, from an area of high concentration to an area of low concentration. Diffusion happens in living systems, for example, it explains the movement of carbon dioxide in leaves.
Osmosis is the movement of water from a high water concentration to a low water concentration through a partially permeable membrane. Plants absorb water from the soil by osmosis through their root hair cells.
Diffusion
Diffusion is a process in which material spreads throughout a liquid or a gas. It is the overall movement of a substance from a region of high to low concentration. It happens because of the random movement of individual particles.
Diffusion is important to living things as it explains how useful materials and waste products can move into and out of cells.
Diffusion gives the effect that the substance is moving from an area of high concentration to an area of low concentration (or 'down a concentration gradient').
Diffusion looks as if it has stopped when the particles are evenly spread out. The animation models how this works when purple potassium manganate(VII) diffuses through water.
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