Facilitated diffusion and active transport are two processes by which cells can move substances across their membranes. Both processes involve the use of proteins to transport substances, and both require energy from the cell to function. However, there are also some key differences between the two processes:
Similarities:
Both facilitated diffusion and active transport involve the use of proteins to transport substances across a cell membrane.
Both processes require energy from the cell to function.
Differences:
Facilitated diffusion is a passive process, which means that it does not require the cell to use energy to actively pump substances across the membrane. Instead, substances are transported down their concentration gradient, from an area of high concentration to an area of low concentration.
Active transport, on the other hand, is an active process that requires the cell to use energy to pump substances against their concentration gradient, from an area of low concentration to an area of high concentration.
Facilitated diffusion can transport substances in either direction, while active transport can only transport substances in one direction (from low concentration to high concentration).
Facilitated diffusion is limited by the concentration gradient of the substance being transported, while active transport is not. This means that active transport can continue to transport substances even when their concentrations are equal on either side of the membrane.