What is diffusion? Include in your explanation "area of high concentration" and "area of low concentration". Does diffusion occur across a membrane, without a membrane, or can diffusion occur in both situations?

Diffusion is the process of small molecules moving from a high concentrated area to a lower concentrated area. For example, in a crowded train station, when a train arrives, people move from the high concentrated area, which is the platform, and move onto the lower concentrated area, which is the trian.

Explanation:

The process of diffusion does not cost any energy, as it happens naturally, and would cost energy to go against it, like trying to go from the train into the platform costs more energy than just going with the crowd into the train. And only small molecules can do this without using energy. Large molecules, like starch, can't do this without using energy.(ATP) hopefully, this helped you, and it would mean a lot to me if you could give me brainliest!