In comparing simple diffusion to facilitated diffusion, you note that:

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Quizplus · Accepted Answer

Both simple and facilitated diffusion require a concentration gradient to move substances from an area of higher concentration to an area of lower concentration. However, only facilitated diffusion requires a specific carrier or protein channel, and neither process requires ATP as they are passive transport mechanisms. Additionally, both processes can only move substances down a concentration gradient, not up.

In Comparing Simple Diffusion to Facilitated Diffusion, You Note That