Across
- 7. : Muscle that helps air move in and out
- 8. : Voice box; produces sound
- 9. : Releasing air out of lungs
- 12. : Blood flow between heart and lungs
- 13. : Liquid part of blood carrying nutrients and hormones
- 14. : Windpipe; carries air to the lungs
- 16. : Flap that prevents food from entering airway
- 18. : Defend the body against infections
- 24. : Gas inhaled for cellular respiration
- 25. : Protein in red blood cells binding oxygen
- 26. : Largest artery carrying oxygen-rich blood
- 27. : Waste gas exhaled by lungs
- 29. : Throat; connects mouth and nasal passages to larynx
- 30. : Carry oxygen using hemoglobin
- 33. : Blood flow to the whole body
- 34. : Sticky fluid trapping dust and pathogens
- 36. : Continuous blood movement in the body
- 38. : Main airway passage inside the nose
Down
- 1. : Tiny blood vessels for gas/nutrient exchange
- 2. : Main organs of breathing; contain alveoli
- 3. : Filters, warms, and moistens incoming air
- 4. : Vessels carrying blood away from the heart
- 5. : Tiny air sacs where gas exchange happens
- 6. : Help blood clot to stop bleeding
- 10. : Two large tubes leading to each lung
- 11. : Breathing air into lungs
- 12. : Membrane covering lungs
- 13. : Rhythmic heartbeat felt in arteries
- 15. : Lower heart chambers pumping blood out
- 17. : Carries deoxygenated blood to lungs
- 19. : Smaller airways branching from bronchi
- 20. : Prevent backflow of blood in veins and heart
- 21. : Carries oxygenated blood from lungs
- 22. : Chest cavity housing lungs and heart
- 23. : Force of blood on vessel walls
- 28. : Process of oxygen exchange and energy release
- 31. : Vessels returning blood to the heart
- 32. : Pumps blood throughout the body
- 35. : Hair-like structures that trap dust and microbes
- 37. : Upper heart chambers receiving blood