Diffusion, Osmosis and Active Transport
Diffusion is the movement of particles from an area of high concentration to an area of low concentration.
Osmosis is the movement of water molecules from an area of high water concentration to an area of low water concentration across a partially permeable membrane.
Active transport is the absorbance of substances against a concentration gradient i.e. from a lower to a higher concentration. This process requires energy from respiration for it to happen.