How does this model support the conclusion that cells need to have a high amount of surface area relative to their total volume?

These gel cubes can be thought of as representing individual cells. As the cubes interact with their surroundings based on the amount of surface area and volume they have, the efficiency movement of substances in and out of cells depends on the two attributes as well. Greater surface area will mean more efficient rates of diffusion, which implies a smaller surface area to volume ratio is ideal for a biological cell.

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