Question

Which of the following events does not occur during exhalation in human beings?

• A. The intercostal muscles pull the ribs inwardly.
• B. The volume of thoracic cavity increases.
• C. High pressure area is created inside the thoracic cavity.
• D. Diaphragm becomes dome-shaped.

Answer 1

The correct option is B The volume of thoracic cavity increases.

During exhalation in human beings, the inter-costal muscles pull the ribs inward and the diaphragm becomes dome-shaped. The volume of the thoracic cavity decreases which creates high pressure inside the thoracic cavity and eventually the air moves out of the lungs.