Answer:
When materials diffuse across a membrane, they move from an HIGHER area of concentration to a LOWER area of concentration along the concentration gradient.
Step-by-step explanation:
A concentration gradient is the process where particles, also called solutes, move through a solution or gas from an area (usually separated by a membrane) with a higher number of particles to an area with a lower number of particles, in other words, from a higher concentration area to a lower concentration until the concentration of substances is uniform throughout.
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