There are two types of transport mechanisms 1.Passive Transport - it is of three types - i. Simple Diffusion ii. Facilitated Diffusion iii.Ion Channels 2.Active Transport - Click here for detailed notes PASSIVE TRANSPORT This type of transport mechanism does not require energy. Movement of molecules occur along the concentration gradient. Types of Passive Transport - Osmosis is a type of Simple Diffusion in which water molecules move from high concentration area to low concentration area through a selectively permeable membrane.