Question

4. Explain about the mechanism of breathing and respiration. ​

Answer 1

Answer:

The action of breathing in and out is due to changes of pressure within the thorax, in comparison with the outside. This action is also known as external respiration. When we inhale the intercostal muscles (between the ribs) and diaphragm contract to expand the chest cavity.

Answer 2

Answer:

During inhalation, the lungs expand with air and oxygen diffuses across the lung's surface, entering the bloodstream. ... During inhalation, the diaphragm is contracted which increases the volume of the lung cavity. During exhalation, the diaphragm is relaxed which decreases the volume of the lung cavity.