Question

1. when molecules spread out, it is called _ and when they spread out using a channel protein, it is called _. 12. when substances move against their gradient, it is called _. it requires a carrier protein and _ transport, and

Explanation:

1. Diffusion is the passive movement of molecules from an area of high - concentration to low - concentration. Facilitated diffusion uses channel proteins to help molecules move down their concentration gradient.
2. Active transport is the movement of substances against their concentration gradient, which requires a carrier protein and energy (usually ATP).

Answer:

1. Facilitated diffusion; Diffusion
2. Active