ANATOMY

Detailed explanation-1: -The process of exhaling carbon dioxide is called expiration. It is a passive process. It occurs when the size of the thoracic activity decreases and the air pressure outside increases. Now the external intercostal muscles relax and the internal intercostal muscles contract.

Detailed explanation-2: -The process of normal expiration is passive, meaning that energy is not required to push air out of the lungs. Instead, the elasticity of the lung tissue causes the lung to recoil, as the diaphragm and intercostal muscles relax following inspiration.

Detailed explanation-3: -In exhalation, the diaphragm moves upward and the chest wall muscles relax, causing the chest cavity to get smaller and push air out of respiratory system through the nose or mouth.

Detailed explanation-4: -Expiration is typically a passive process that happens from the relaxation of the diaphragm muscle (that contracted during inspiration). The primary reason that expiration is passive is due to the elastic recoil of the lungs.

Detailed explanation-5: -Expiration can either be quiet or forced. Quiet expiration is a passive process occurring at rest, whereas forced expiration is an active process that occurs during exercise.