Ch. 18 sec. 4 Answers

BIOGEOCHEMICAL CYCLES

1. What percent of a cell is made up of water?

2. What are the three important processes in the water cycle?

Condensation

3. Define transpiration.

4. What are three ways animals (You) release water?

5. What are the two processes that form the basis of the short-term carbon cycle?

6. What has happened to the concentration of carbon dioxide in the atmosphere over the last

150 years?

7. What are fossil fuels (coal, oil, natural gas…)?

8. What percent of the atmosphere is made up of nitrogen?

9. What is nitrogen fixation?

10. What do most organisms rely on to transform nitrogen gas into a usable form?

11. Besides in the bodies of dead organisms, what else produced by animals can contain

nitrogen?

12. Describe the process of ammonification.

13. Describe the process of nitrification.

14. Describe the process of denitrification.

15. What is the phosphorus cycle?