What is the function of the thorax in respiration?

What is the function of the thorax in respiration?

• A. Gas exchange in alveoli.
• B. Inspiration and expiration.
• C. Filters air.
• D. Produces mucus.

Answer: (B)

The thorax drives ventilation by changing the chest’s volume through the diaphragm and rib movements. When the diaphragm contracts and the rib cage expands, the thoracic space increases, lowering lung pressure and drawing air in (inspiration). Relaxation of these muscles reduces thoracic volume, increasing pressure and pushing air out (expiration). Gas exchange happens across the alveolar walls inside the lungs, not in the thorax itself, and air filtration or mucus production occurs in the airways and nasal passages, not due to the thorax.

The thorax drives ventilation by changing the chest’s volume through the diaphragm and rib movements. When the diaphragm contracts and the rib cage expands, the thoracic space increases, lowering lung pressure and drawing air in (inspiration). Relaxation of these muscles reduces thoracic volume, increasing pressure and pushing air out (expiration). Gas exchange happens across the alveolar walls inside the lungs, not in the thorax itself, and air filtration or mucus production occurs in the airways and nasal passages, not due to the thorax.