Form alveoli or alveoli place where gas exchange between air and blood vessels, and nature physiological and anatomical of alveoli allow this exchange that alveoli with thin wall too, and is surrounded by a network of capillaries area of about 70 m containing cells secrete a special substance called Sir Vaktant (keeps the rubber and breadth of lung), and Dermanyssus gallinae cells, tissues private, and holes all these factors working to facilitate the passage of air to and from the alveoli and go through the process of gaseous exchange in four stages:
- Gas exchange between the air conditioner and alveoli, called pulmonary ventilation.
- The exchange of oxygen and carbon dioxide between the alveoli and capillaries.
- Transfer of oxygen and carbon dioxide in the blood.
- The exchange of oxygen and carbon dioxide between the capillaries and cells.
