Question

the directional movement of ions by facilitated diffusion through protein channels is determined by ____________. multiple choice the formation of a secretory vesicle the availability of atp the electrochemical gradient of the ion being transported

Explanation:

Facilitated diffusion of ions through protein - channels is a passive process. It depends on the electrochemical gradient of the ion, which is a combination of the concentration gradient and the electrical potential gradient. Secretory vesicle formation is related to exocytosis and not to the direction of ion movement in facilitated diffusion. ATP is used in active transport, not in passive facilitated diffusion.

Answer:

the electrochemical gradient of the ion being transported