The Extraordinary Exchange

A net of blood vessels (so fine that the blood must squeak through one cell at a time) is laced tightly around each air sac (alveolus). The alveolar walls here are as thin as soap bubbles about to burst. This ingenious design allows oxygen to pass easily from the incoming breath, through the thin shared wall of the air sac and blood vessels and finally into the blood stream.

While the blood is sucking up oxygen from the air sac, it simultaneously gives up its carbon dioxide into that same tiny sac. Carbon dioxide is spent fuel that now must be carried away in the air about to be exhaled from all alveoli.

Your blood at that point has been refreshed with a new supply of oxygen and is ready to resume its unending duties on your behalf. It is the extraordinary exchange of gases in this inner sanctum that fuels all that you do, all that you are.

Be well. Breathe beautifully.

Link: The Path From Throat To Lungs