Question

What does a surface area ratio of 3:1 mean for a cell’s ability to get materials across its membrane, compared to the cell with a ratio of 6:1? Will definitely be giving out medals! :3

Answer 1

That ratio means SURFACE AREA to VOLUME of the cell. Surface area pertains to the area outside/around the cell and volume is the amount of space inside. Cells need to be small, meaning ratio of 3:1, in order for them to easily diffuse substances in and out of the cell. As a cell grows, diffusion becomes less efficient since there is more membrane to penetrate. As the cell diffusion becomes less efficient, resulting in cell processes slowing down, the cell will then stop growing. It needs to divide into two smaller cells in order to have a larger surface area to volume ratio, in order to diffuse substances efficiently again.

P.S. It's just how I understand it. :)