Question

__________ is a muscular sheet that helps in breathing by increasing and decreasing the volume of the thoracic cavity.

• A. Diaphragm
• B. Muscle Flap
• C. Muscular membrane
• D. Blood-brain barrier

Answer 1

The correct option is A

Diaphragm

During inhalation, the diaphragm contracts and becomes flat. This increases the volume of the thoracic cavity and provides more space for the lungs to expand. The opposite happens during exhalation, where the diaphragm relaxes and becomes dome-shaped. This decreases the volume of the thoracic cavity and forces air out of the lungs.