March 14th - Onion Cell Osmosis Lab

Here is the lab we completed today looking at osmosis and red onion cells.
Click here to access lab.

Background:

A substance that dissolves in another substance is called a solute, and the more plentiful substance that does the dissolving is called the solvent.  In living things, water is the solvent.  The mixture of solute and solvent is called a solution. Solute and solvent tend to diffuse from areas where their concentration is high to areas where their concentration is lower.  When water moves from higher concentration of water to lower concentration of water through a cell membrane, it is called osmosis. 

Here is the cell before the salt solution was added.

Here is the cell after the salt solution was added.

Notice the decrease in size of the vacuole as the water is diffused out of it.