Facilitated diffusion

Biological process

Facilitated diffusion (also known as facilitated transport or passive-mediated transport) is the process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins. Being passive, facilitated transport does not directly require chemical energy from ATP hydrolysis in the transport step itself; rather, molecules and ions move down their concentration gradient according to the principles of diffusion. Facilitated diffusion differs from simple diffusion in several ways: The transport relies on molecular binding between the cargo and the membrane-embedded channel or carrier protein.

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