What assists larger particles in facilitated diffusion through the cell membrane?

Facilitated diffusion is a process that helps larger or polar molecules move across the cell membrane without the expenditure of energy. This process relies on specific proteins embedded in the cell membrane known as carrier proteins. These proteins bind to the larger particles, such as glucose or amino acids, and help transport them across the lipid bilayer by undergoing a conformational change. This is crucial because the cell membrane is selectively permeable, allowing certain substances to pass while blocking others.

Energy from ATP is not involved in facilitated diffusion; this process is a passive transport mechanism that utilizes the concentration gradient. Aquaporins specifically facilitate the movement of water molecules across the membrane, rather than larger particles. Passive enzymes is a term that does not accurately describe any known mechanism of transport across membranes. Thus, carrier proteins are essential for the movement of larger particles during facilitated diffusion.