what is diffusion and facilitated diffusion?
Answers
Diffusion is the movement of molecules from an area where the molecule is in high concentration to an area where the molecule is in lower concentration. Facilitated diffusion is the movement of a molecule from an area of high concentration to an area of lower concentration with the help of a protein channel or carrier.
Answer:
Facilitated Diffusion
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.[1] 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 reflecting its diffusive nature.
Simple Diffusion
In biology, simple diffusion is a form of diffusion that does not require the assistance of membrane proteins. In essence, the particle or substance moves from higher to lower concentration. However, its movement does not need a membrane protein that will help substances to move downhill. In other science disciplines, such as physics and chemistry, diffusion is defined basically as the “spreading out” of the objects from the initial area of higher concentration. In a biological system, the same principle applies but the process involves a semipermeable biological membrane.