what is the role of diffusion in gas exchange?
Diffusion is the spread of molecules from regions of high to regions of low concentration. Molecules that are concentrated will randomly move about(diffuse) and eventually, after colliding, they get distributed uniformly, reaching an equilibrium. In terms of gas exchange, the respiratory gases oxygen and carbon dioxide are exchanged at the thin, moist respiratory surface called alveoli, air sacs located in the lungs. These are surrounded by blood capillaries, thin-walled vessels which allow...
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