3. Explain the mechanism of breathing in humans.
Answers
Explanation:
Mechanism of Breathing in Human beings: Breathing is a complex mechanical process that involves muscular movement which in turn alters the volume of the thoracic cavity and thereby that of the lungs.
Breathing occurs involuntarily but its rate is controlled by the respiratory centre of brain. The space of thoracic cavity increases or decreases by outward and inward movements of the ribs caused by external intercostal and internal intercostal muscles.
This action is also assisted by the contraction and expansion of the diaphragm. The floor of the thoracic cavity is completely closed by diaphragm. It is a thin muscular septum separating the abdominal and thoracic cavities.
The inhalation and exhalation of the air take place continuously in the respiratory system.Inspiration or inhalation is concerned with the takingin of atmospheric air or oxygen into the thoracic cavity. Expiration or exhalation is concerned with the expelling of carbon dioxide from lungs. It takes place when the volume of the thoracic cavity decreases and the pressure of the contained air in the thoracic cavity increases.
Answer:
The mechanism of breathing is the process by which oxygen rich gas is inhaled and the carbon dioxide is exhaled . During the inspiration ribs move up and outwards and the diaphragm moves down . This movement increases space in our chest cavity and air rushes into the lungs .
Explanation: