Question

ion channels a type of facilitated diffusion uses _______________ to move particles across/through the cell membrane. nothing (no help) vesicles membrane proteins none of the above

Explanation:

Ion channels are a type of membrane - bound proteins that enable facilitated diffusion of particles across the cell membrane. Vesicles are involved in bulk transport, not facilitated diffusion through ion channels, and diffusion without help is simple diffusion, not facilitated diffusion.

Answer:

C. Membrane Proteins