Biology Puzzle

3. Consists of all waters present in the Earth
8. Homogeneous mixture of gases on Earth
10. Highly poisonous gas with three atoms of oxygen
11. Introduction of pollutants to environment
12. Dark organic material in the soil
13. Falling of water from clouds to Earth in liquid or solid state
16. Example of bacteria in nitrogen-fixation
17. Another word for burning; exothermic redox
18. Organisms feeding on dead decaying matter
19. Movement of air
21. Gaseous envelope of a celestial body
22. Release of water from leaves of plants
23. Physical environment where organisms are inter-related
24. Production of energy in living organisms typically with inhale of O2 and exhale of CO2

1. Uppermost soil layer with most organic matter
2. Glass structure to grow tender plants to protect them from weather, mostly cold weather
4. Change of state from liquid to gas
5. Second layer of atmosphere as you go upward
6. Breaking of dead matter into simpler form
7. Clearing or thinning of forests by humans
9. Process by which plants use sunlight, CO2 and water to make their food
14. Variety of life on Earth
15. Oxidation of ammonia to nitrites
20. Organism causing disease(s); germ
25. Fog intensified with smoke