Active Transport
Active transport is the movement of dissolved molecules into or out of a cell through the cell membrane, from a region of lower concentration to a region of higher concentration. The particles move against the concentration gradient , using energy released during respiration .
Osmosis
Osmosis is defined as the spontaneous movement of solvent molecules from a region of low solute concentration to a region of high solute concentration through a semipermeable membrane in order to equalize their concentrations on both sides of the membrane.
Diffusion
Diffusion is defined as the movement of atoms, ions, and molecules from a region of high concentration to a region of low concentration, or ‘down their concentration gradient’. The word ‘diffusion’ is derived from the Latin word, ‘diffundere’, meaning ‘to spread out’.