Across
- 5. Some bacteria obtain energy by converting nitrates into nitrogen gas, which is released into the atmosphere
- 9. Any nutrient whose supply limits productivity
- 11. or small pieces of dead and decaying plant and animal
- 12. Each step in a food chain or food web is called a
- 14. the first producers of energy-rich compounds
- 16. Total amount of living tissue within a given trophic level
- 18. harness solar energy to build living tissues through
Down
- 1. are powered by the flow of energy
- 2. There, primary producers are usually tiny floating algae
- 3. are elements that an organism needs to sustain life
- 4. are organisms that rely on other organisms for energy and nutrients
- 6. are models that show the relative amount of energy or matter contained within each trophic level in a food chain or food web.
- 7. Ecologists call this network of feeding interactions, through which both energy and matter move
- 8. only certain types of bacteria can convert nitrogen gas into ammonia
- 10. harness chemical energy from inorganic molecules
- 13. must acquire energy from other organisms
- 15. No living thing can create energy except...
- 17. series of organisms in which energy is transferred from one organ-ism to another