Surface Area to Volume Ratios

Explain why surface-area-to-volume ratios are important in affecting a biological system’s ability to obtain necessary resources or eliminate waste products AND Explain why smaller cells have a more favorable surface area-to-volume ratio for exchange of materials with the environment.

This is a simple math problem. Let’s take a look at cuboidal cells. As the volume of a cell increases, so does its surface area. the relation between these two numbers is exponential, so as surface area increases, the volume increases at a greater rate. 

http://www.tiem.utk.edu/~gross/bioed/bealsmodules/area_volume.html

As a result of this, more material can enter the cell [because of the increased SA] but will take a greater time to reach the center as the volume has increased drastically. So, in a cell with greater SA and V, it will take a greater time to receive necessary resources and to eliminate waste products. This is why small cells are more efficient; smaller cells have a more favorable surface area-to-volume ratio for exchange of materials with the environment.

This YouTube video below shows this concept in action.