Chapter 10

2. The process by which organisms convert energy stored in food into usable energy.
4. The natural process by which ecosystems develop and change over time.
5. Chain A sequence of organisms through which energy flows in an ecosystem.
6. The role and position an organism has in its environment.
8. Productivity The rate at which plants produce energy in an ecosystem.
9. The variety of life within an ecosystem or the entire Earth.
11. Cycle The cycle through which carbon is exchanged between organisms and the environment.
13. The environmental sphere that includes all living organisms.
14. Cycle The cycle through which nitrogen is converted into forms usable by living organisms.

1. Level The position of an organism in the food chain.
3. The process by which plants convert sunlight into energy.
7. The specific environment where an organism lives.
10. Organisms that break down dead material and recycle nutrients.
12. A large geographic area characterized by specific plant and animal life.
15. A community of organisms interacting with their physical environment.