Passive Transport
Passive transport is a movement of biochemical and other atomic or molecular substances across the Cell membrane without the need of energy input. Unlike the Active transport, it does not require an input of cellular energy, because it is instead driven by the tendency of the system to grow in entropy. Passive Transport relies on the innate permeability of the cell membrane and its component protein and lipids. There are four main types of Passive Transports. One of the most common types of Passive Transport is Osmosis, which is solely responsible for moving water through a cell's membrane. Other kinds of particles can also move through the cell membrane as well. They are usually very small molecules such as oxygen and simply pass between the spaces in the lipid bilayer of a cell's membrane. Another type of passive transport is Diffusion. Diffusion is the overall movement of material from an area of higher concentration to an area of lower concentration. Facilitated Diffusion is the carrier-medicated transport of large molecules through the cell membrane using transport protein embedded within the cell membrane. Filtration is the movement of solute molecules and water across a membrane by normal cardiovascular pressure. The passive transport is a virtual process that the cells need to survive.