Question

How is facilitated diffusion and diffusion through ion channels similar?

Answer 1

facilitated diffusion is one type of transport through ion channels.

Explanation:

if transport through ion channel is done down concentration gradient (high to low concentration) then it is facilitated diffusion, and if it is done up concentration gradient (low to high concentration), then it is active transport which requires ATP.

Here is a video which illustrates how membrane proteins are involved in the process of facilitated diffusion.