The Air Bags
- BREATH IN — your body gets oxygen from the air. Rib muscles contract to pull ribs up and out. The DIAPHRAGM muscle contracts to pull down the lungs. Tissue expands to suck in air.
- BREATH OUT — you get rid of other gases that your body does not need. Rib muscles relax. The Diaphragm muscle relaxes. Tissue returns to resting position and forces air out.
- KidsHealth: Your Lungs & Respiratory System
- Franklin Institute: Respiratory System
- Your Gross and Cool Body: Respiratory System