Across
- 2. Part of the respiratory system, after the trachea
- 3. A muscle under the lungs, helps you breathe
- 6. A gas in air that humans need to survive
- 8. The system which brings blood around your body.
- 9. Take blood back to the heart.
Down
- 1. The system that allows you to inhale and exhale air.
- 4. Carry oxygen-rich blood away from the heart.
- 5. The pump of the circulatory system
- 7. The windpipe that allows air to travel to the lungs.