PHYSIOLOGY OF RESPIRATION
The physiology of respiration involves the complex processes that enable the exchange of oxygen and carbon dioxide between the body and the environment. Here's a detailed explanation: *Stages of Respiration:* 1. Breathing (Ventilation): inhalation and exhalation of air. 2. Gas exchange: oxygen diffuses into the blood, and carbon dioxide diffuses out. 3. Transport: oxygen-rich blood is transported to tissues, and carbon dioxide-rich blood returns to the lungs. 4. Cellular respiration: oxygen is used for cellular metabolism, producing energy. *Mechanisms of Breathing:* 1. Diaphragm contraction: increases thoracic cavity volume. 2. Intercostal muscle contraction: expands rib cage. 3. Lung expansion: air enters through mouth/nose, trachea, bronchi, and bronchioles. 4. Alveoli: tiny air sacs where gas exchange occurs. *Gas Exchange:* 1. Oxygen diffuses from alveoli into blood. 2. Hemoglobin binds oxygen, forming oxyhemoglobin. 3. Carbon dioxide diffuses from blood into alveoli. 4. Exha...