Question

Describe the mechanism of breathing in human beings how lungs are designed in human beings to maximize the area for exchange of gases

Answer 1

70 per cent nitrogen
21 per cent oxygen

Answer 2

♤ In the lungs, the air passage that divides into smaller and smaller tubes called bronchi which form bronchioles .

♤ The bronchioles terminate in the balloon like structure called alveoli.

♤ The alveoli present in the lungs provide maximum surface for exchange of gases.

♤ The alveoli have very thin walls and contain an extensive network of blood vessels to facilitate exchange of gases.