Fourth Class: Diffusion and Osmosis

In our fourth class we looked at the processes of Diffusion and Osmosis. Diffusion is the way molecules will exit or enter a semipermeable surface to balance the pressure on either side of the surface.  For example, when a bottle of perfume is opened, the molecules will slowly shoot out as they are bouncing all over the place.  In balloons, after a while they shrink and no longer float on their own.  This happens as helium molecules rush out of the thin material and it becomes heavier than the air around it.  Osmosis is a similar process, but is only used to describe water molecules.  In cells water molecules can move in and out through the cell wall because it is semi-permeable.  This is important especially to human life, because it is the reason we drink water.  The water enters our blood system and hydrates the blood cells.  Water can move like this due to its size and it's innate ability to balance the pressure on either side or a membrane.  Osmosis and diffusion are important in life because of their significance in the movement of molecules.