What part of your body has a volume that gets bigger when you take a deep breath?

The lungs are the part of your body whose volume increases when you take a deep breath.

Explanation:

The lungs are soft, spongy organs located inside your chest. They don’t have muscles of their own but expand and contract with the help of the diaphragm and the muscles between your ribs (intercostal muscles).

When you take a deep breath in (inhalation):

• The diaphragm contracts and moves downward, creating more space in the chest cavity.
• The rib cage expands outward and upward, further increasing the chest volume.
• As a result, the lungs expand and fill with air, increasing their volume.

When you breathe out (exhalation):

• The diaphragm relaxes and moves upward.
• The rib cage moves inward.
• The lungs shrink back to their resting size as air flows out.
• This process is called pulmonary ventilation or simply, breathing.