Across
- 4. this gas is found in fluorescent tubes
- 5. if I eat the animal that eats the plant, what level am I?
- 7. the release of energy from food
- 9. we make our own food
- 10. used to break down dead material and return nutrients to the soil
- 13. the only type of plants with nitrogen fixing bacteria in their roots
- 14. makes the soil very fertile
Down
- 1. humans fall in this category because we eat both plants and meat
- 2. carbon gas is returned to the environment by this process
- 3. this type of soil holds a lot of water
- 6. dry ice
- 8. the same amount of this gas we breathe in is the same amount we breathe out
- 11. roots of trees grow into this layer
- 12. makes your voice squeaky