Across
- 3. ______ of fuels such as petrol and diesel released nitrogen dioxide
- 7. released from anthers into the air irritate the respiratory system
- 10. fine branches of trachea system of insects
- 11. respiration occurs when glucose combined with oxygen to produce energy, carbon dioxide and water
- 13. carbon dioxide released by body cells diffuses into the blood ___________
- 17. an inflammation of the bronchus caused by tar and irritants in cigarette smoke
- 18. breathing pores in insects
- 19. cigarette ____sticks to and kill cells in the air passage
Down
- 1. volume of _______ cavity decreases during exhalation
- 2. of gases occurs in the alveoli
- 4. is bright red in colour and is an unstable compound
- 5. the condition of the alveoli in the lungs which are damaged by harmful substances in the air
- 6. of the alveolar structure increase the efficiency of gaseous exchange
- 8. chemical substances that caused cancer
- 9. the process of inhaling and exhaling air
- 12. symptoms are shortness of breath, wheezing and coughing
- 14. moves downwards and flattens during inhalation process
- 15. moves upwards and downwards during inhalation
- 16. thin and flat projections in filaments of fish gills