Question

What happen when air enters the alveoli of the lung

Answer 1

Answer:

The alveoli is filled with blood capillaries (which come from the pulmonary artery)

which have CO2 and water vapour collected from all the cells in the body.

When air reaches the alveoli, This CO2 and water vapour diffuse out, and fresh O2 diffuses into the blood.

This Oxygenated blood is carried to the heart(via pulmonary vein) so that it can be pumped to the rest of the body.

Answer 2

Explanation:

1. in the lungs the air passage (wind pipe)divides into smaller tubes,called bronchi which in turn divides n form bronchioles.
2. the bronchioles terminate in balloon-like structures, called alveoli. each lung contains 300-350 millions of alveoli.
3. the alveoli present in the lungs provide maximum surface for the exchange of gases.
4. the alveoli have very thin walls and contains in extensive network of blood vessels to facilitate exchange of gases.