In simple words breathing is defined as the exchange of gases like inhalation of oxygen and exhalation of carbon dioxide, how this process occurs in details we call it mechanism (in a systematic manner). There are some voluntary actions and involuntary actions here exchange of gases is involuntary action that felcitates our survival.
Mechanism
The intake of oxygen from atmosphere is very active process. The thoracic Cavity increases in volume and the air pressure is lowered we can say inspiration or inhalation took place. Intercoastal muscle contraction increases the volume of thoracic cavity, at the same diaphragm also Contactracted and Increasing the size of thoracic cavity thus expanding the lungs and decreasing the air pressure inside the lungs, after that the pressure become equal and air lashes inside the lungs. This was about inspiration or inhalation. Now what is Expiration? It states that opposite of inspiration, it is the expulsion of CO2 from the lungs through the 馃憙 nose. During this episode the abdominal and diaphragm muscles relaxed at the same time associated musles of the ribs contractcontract. After that the lung pressure increases and the volume of chest cavity gets lowered and leads the air goes out through nose.
Now i am gonna discuss here mechanism of breathing and exchange of gases. First we need to know what is diffusion the movement of gases or gaseous molecules from the region of higher concentration to the region of lower concentration, exchange of gases occurs through the diffusion process in the alveoli or alveolus.
The presence of oxygen in the blood is transported in two ways one mixture of O2 and hemoglobin or oxyhemoglobin and second one is oxygen solution in plasma. Higher concentration of hemoglobin leads to the dissociation process. When the o2 is supplied to the tissues we call it internal respiration, in this process the o2 separation from hemoglobin, further o2 broke down into co2, energy and water. At the same time co2 is removed from the tissues and energy is utlized.
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