Question

what causes ribcage to expand?​

Answer 1

Answer:

During normal breathing, contraction of the major inspiratory muscle, the diaphragm, produces both rib cage expansion and a downward movement of the diaphragm. These movements cause the pressure around and in the lung to become negative relative to atmosphere.

Answer 2

Answer:

During normal breathing, contraction of the major inspiratory muscle, the diaphragm, produces both rib cage expansion and a downward movement of the diaphragm. These movements cause the pressure around and in the lung to become negative relative to atmosphere.