How are the lungs designed in human beings to maximise the area for exchange of gases?
Lungs are the two pairs of organ lies in the thoracic cavity on the sides of the heart. The trachea divides into two tubes- major or primary bronchi. Major bronchus enters the right lung and second one enter into the left lung. Then bronchus divides into secondary bronchi further extends into three lobes of right lung and subdivides into small tertiary bronchi and finally they divided into smaller bronchioles (wall consists of epithelium). Then, these terminal bronchioles divided into alveolar ducts enters into alveolar sacs. This respiratory pathway within the lungs are known as respiratory tree.
Alveoli are pouch like structure present on the each nerve ending and possess network of blood capillaries or covers very huge amount of surface of the human body, which increases the surface area for the exchange of gases. That is how, the lungs are designed in human beings to maximise the area for exchange of gases- uptake of oxygen by blood and release of carbon dioxide by blood.
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