Across
- 6. the act of breathing in gas to fill the lungs
- 9. side of the heart that is oxygen-poor (blue)
- 11. the gas that is exhaled by mammals
- 13. blood vessels that connect veins and arteries
- 15. major organs of the respiratory system
- 16. a flap of cartilage at the top of the trachea that covers the opening of the windpipe
- 18. windpipe of the respiratory system
- 19. smaller branches of the major air passages that extend off of the trachea
Down
- 1. involved in swallowing, breathing, and voice production
- 2. blood vessels that carry blood away from the heart
- 3. the gas that is inhaled by mammals
- 4. the number of chambers in the heart
- 5. the act of breathing out gas to expel the lungs
- 6. during inhalation, the thoracic cavity _____ in size
- 7. many tiny air sacs of the lungs which allow for gas exchange
- 8. blood vessels that carry blood towards the heart from the lungs
- 10. during exhalation, the thoracic cavity _____ in size
- 12. major air passages of the lungs which branch off of the trachea
- 14. side of the heart that is oxygen-rich (red)
- 17. the number of ventricles or atriums in the heart
- 20. major organ of the cardiovascular system