system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are cells so small and why can't they be huge?
gpt
Because as cells get larger, their interior mass increases faster than the surface area of the cell membrane. This means that at one point, the amount of membrane would not be sufficient for servicing the entire cell interior. Not enough oxygen/water/sugar could enter the cells through the limited protein "doors."