Molecules move down their concentration gradient in facilitated diffusion through channels of proteins.
For most molecules, movement through the membrane, with a significant rate, is only possible by the presence of transporter proteins (integral membrane proteins, which recognize substances with a high specificity, accelerating their translocation) or channels of proteins.
Transport proteins allow the facilitated diffusion of molecules, moving them along the free energy gradient (concentration gradient, charge gradient, or both), in the direction of thermodynamic equilibrium.
When a carrier protein binds to a solute, the protein changes shape in such a way that it carries the solute to the other side of the membrane.
Facilitated diffusion is similar to simple diffusion, since the molecules move from a region of higher to a lower concentration of solutes.
For example, by facilitated diffusion, chlorine ions move down their concentration gradient into the cell through chlorine channels.
Therefore, we can conclude that many molecules are assisted by transporter proteins for their diffusion through the plasma membrane, a process known as facilitated diffusion, where the molecules descend through their concentration gradient.
Learn more here: https://brainly.com/question/22811521
