Question

In detail, what processes do the respiratory system and the muscular system go through to work together?

Answer 1

Contraction and relaxation of muscles help in breathing in and breathing out.

Explanation:

Intercostal muscles of rib cage and phrenic muscles of diaphragm are help in breathing movements.

Inspiration involves:
1. Contraction and flattening of diaphragm
2. Contraction of external intercostals raises the ribs, sternum is pushed forward as a result

Expiration is normally a passive process but forceful exhalation can be done by contraction of two more muscles:
1. Abdominal muscles and
2. Internal intercostal muscles