Respiratory system
Across
- 2. Filling the lungs with fresh air.
- 5. The main branch of the trachea.
- 6. Process by which the body cells use oxygen.
- 7. Spongy, saclike respiratory organs in the chest cavity.
Down
- 1. Tube that joins the bronchi to the lungs.
- 3. Tiny, thin walled sac in the lungs where the exchange of gases take place.
- 4. Muscle that separates the abdominal and the chest cavities.