Ecology Part 1 Review

3. Plants play a role in the carbon cycle through this process-removing CO2 from the atmosphere.
6. In most of the biogeochemical cycles, this process helps to return nutrients to the soil-as dead organisms are broken down.
8. _______ factors include nonliving factors of an ecosystem, such as sunlight, soil, and water.
10. These organisms help to make nitrogen usable by plants.
11. Sulfuric acid falls to the ground from our atmosphere as _____.
13. Without nitrogen ________, plants and animals would not be able to obtain the important nutrient.
14. All energy starts in the _____, then moves to producers-which occupy the first trophic level.
15. Animals play a role in the carbon cycle through this process-taking in O2 and exhaling CO2.

1. Clouds form in our atmosphere through this process.
2. The phosphorous cycle is unique in that it is largely a rock process, and never enters the ____________.
4. Sulfur enters the atmosphere through oceanic bacteria, burning of fossil fuels, and through these.
5. _______ factors include living organisms, such as animals and plants.
7. Two species cannot occupy the same _______, as one will eventually be out-competed.
9. Humans can use this to help plants obtain nitrogen and phosphorous when there is not sufficient levels in the soil.
12. As humans, we are __________, since we cannot make our own food for energy.