Why Are Cells So Small

In this lab, we decided to investigate an important fact that normally goes unquestioned: why are cells so small? Would it be more efficient if everyone were just made up of one or two huge cells? A source of energy and molecules are required by all living organisms, which means that the amount of the cell that is able to receive molecules is important. The group’s hypothesis was that “cells are small because small cells have a larger surface area to volume ratio”, which is important because a larger surface area allows for more molecules to diffuse at one time. The group created cells made out of blocks of agar-phenolphthalein. This allowed a simple indicator of pH, since phenolphthalein turns magenta when it comes into contact with a base.
The prisms all had varying measurements; one measured 1x1x3 cm, another 2x2x3 cm, a third at 4x2x3 cm, and finally a single cube, which measured 3x3x3 cm. A 0.4% sodium hydroxide solution (a base) was poured into a beaker to begin testing the claim. After soaking in the solution for five minutes, each “cell” was removed and cut in half. The group measured how far the base travelled into each model by comparing the magenta color to agar’s normal off-white. Each prism had very similar measurements; the sodium hydroxide travelled approximately 4 millimeters into the cell. This supports the claim, though, since 4 millimeters takes up more of the smaller cell models than it does in the larger ones. It also shows that the rate of diffusion is the same, regardless of a cell’s size, since its makeup doesn’t