What part of a cell controls water movement into and out of the cell?

If you know the answer, I would truly appreciate it if you answered my question. I am not sure if it is the cell membrane or not.

Furthermore, I am doing an experiment that demonstrates osmosis. We are using an egg to represent the cell. What part of the egg controls water movement into and out of the egg?

Thank you very much!What part of a cell controls water movement into and out of the cell?
it is in fact the cell membrane