Answer:
1. diaphragm 2. the lungs 3a. carbon dioxide 3b. ciculatory system 4. the respitory stsem. 5. Tissues 6. capilaries 7. inhale
8. body systems 9. blood cells. 10. organs 11. the skeletal system. 12. arteries 13. oxygen 14. muscular system. 15. Alveoli 16. exhale 17. the heart. 18. veins
Step-by-step explanation: