This is a simulation of how osmosis works. The red line in the center of the area is the cell membrane, the small black dots are water molecules and the large ones are proteins and fats. All the water starts outside the cell and all the proteins and fats start inside of it. As you will notice, the proteins and fats are too large to fit through the membrane, but the water molecules can pass freely and easily. Over time, the concentration of water molecules outside and inside the cell will become the same. Occasionally in this simulation a water molecule might drift back into the cell accidentally and cause the concentration of water inside the cell and outside to differ, but you get the point. This is how osmosis works.
