Question

multiple choice question
what is diffusion?
the movement of molecules through a permeable barrier, regardless of their concentration on either side of the barrier
the movement of molecules from an area of lower concentration to an area of higher concentration
the movement of molecules from an area of higher concentration to an area of lower concentration

Explanation:

Diffusion is the passive movement of molecules from an area of higher concentration to an area of lower concentration down a concentration gradient.

Answer:

The movement of molecules from an area of higher concentration to an area of lower concentration