Explain diffusion and facilitated diffusion and provide an example for each in a biological context.

Explain diffusion and facilitated diffusion and provide an example for each in a biological context.

• A. Diffusion moves down concentration gradient with no energy; facilitated diffusion uses proteins but no energy.
• B. Diffusion requires pumps; facilitated diffusion uses energy.
• C. Diffusion moves against gradient; facilitated diffusion uses energy.
• D. Diffusion uses transport proteins; facilitated diffusion moves down gradient.

Answer: (A)