Facilitated diffusion is a kind of <u>passive diffusion</u>* that utilizes a <u>carrier protein/channel proteins in the cell bilayer</u> that lets molecules pass untouched by the hydrophobic bilayer. This is a common form of transport for <u>polar molecules</u> like <em>carbohydrates (glucose for this question)</em>, <em>amino acids, ions</em>, etc. Glucose transporters or GLUT bind specific molecules from outside of the cell membrane then transport it inside the cell by undergoing a conformational change in shape.
These process usually <u>happens in red blood cells.</u>
*Passive diffusion is a kind of cell transporting mechanism that <u>doesn't require energy or the use of ATP</u>. It either diffuses freely or with the use of proteins.