THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -When the lungs inhale, the diaphragm contracts and pulls downward. At the same time, the muscles between the ribs contract and pull upward. This increases the size of the thoracic cavity and decreases the pressure inside.

Detailed explanation-2: -Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges. This contraction creates a vacuum, which pulls air into the lungs. Upon exhalation, the diaphragm relaxes and returns to its domelike shape, and air is forced out of the lungs.

Detailed explanation-3: -Answer 2: The difference between inhalation and exhalation is that size of the chest cavity increase in inhalation and decreases in exhalation.

Detailed explanation-4: -Inspiration occurs when the diaphragm and the external intercostal muscles contract. Expiration occurs when the diaphragm and the intercostal muscles relax. The contraction or relaxation of muscles around the lungs changes the entire volume of air inside the lungs, and so does the pressure.