Facilitated diffusion is a process by which molecules are transported across the plasma membrane with the help of membrane proteins.
It is a type of passive transport in which no energy from the cell is required for the process because a concentration gradient exists that allows movement of particles without expending cellular energy.
Materials diffuse across the cell membrane with the help of membrane proteins some of which are known as carrier proteins.
Membrane proteins are proteins that are attached to, or associated with the membrane of a cell or an organelle.
