The Impact of Diffusion and Osmosis

Though diffusion and osmosis are primarily subjects of physics and chemistry, they have an enormous impact on biological systems. Unless a cell have a method of actively “pumping” compounds into or out of them, then passive diffusion is the only method. For instance, oxygen from the air sacs in the lungs passively diffuse into the red blood cells. There is no pumping mechanism. Also, many cells gain some nutrients and lose some waste products only through passive diffusion.

Osmosis is also pervasive in biological systems. The method by which nitrogenous waste is removed from human kidneys is based on osmosis. Also, the physiology of most aquatic organisms is dominated by methods of maintaining some form of osmoregularity in relation to the changing environment.