Which statement correctly describes Facilitated Diffusion?

Which statement correctly describes Facilitated Diffusion?

• A. It Moves Substances Against Their Gradient Using Energy
• B. It Always Involves Energy Input From The Cell
• C. It Requires Membrane Proteins To Help Larger, Charged Molecules Pass Down Their Concentration Gradient
• D. It Only Occurs In Plant Cells

Answer: (C)

Facilitated diffusion is a passive transport process where substances move down their concentration gradient with help from membrane proteins. Membrane proteins such as channel proteins or carrier proteins provide a door for specific molecules that can’t cross the lipid bilayer on their own, especially larger or charged ones. Because the movement is driven by the existing gradient, no cellular energy (like ATP) is required. That’s why the description of facilitated diffusion as involving membrane proteins to help larger, charged molecules pass down their concentration gradient is the best fit. It’s not about pushing substances uphill or using cellular energy, and it doesn’t restrict the process to plant cells.

Facilitated diffusion is a passive transport process where substances move down their concentration gradient with help from membrane proteins. Membrane proteins such as channel proteins or carrier proteins provide a door for specific molecules that can’t cross the lipid bilayer on their own, especially larger or charged ones. Because the movement is driven by the existing gradient, no cellular energy (like ATP) is required. That’s why the description of facilitated diffusion as involving membrane proteins to help larger, charged molecules pass down their concentration gradient is the best fit. It’s not about pushing substances uphill or using cellular energy, and it doesn’t restrict the process to plant cells.