2. Define ecosystem.
Community of organisms and their abiotic environment.

3. Define food chain.
Food chain: the pathway of energy being transferred through various stages as a result of the feeding patterns of a series of organisms.

4. Compare primary and secondary succession.
Primary: no life before
Secondary: replaces previous life

5. How much energy is available for the level above on an energy pyramid?
10%

6. Define symbiosis
Two or more species live together in a close, long-term association.

7. What is commensalism?
One organism is helped, the other is not helped or hurt.

8. What is acid rain?
When sulfur combines with water vapor, the rain lowers the pH of the soil and water sources.

9. What are renewable resources?
Resources that are replenished naturally.
Wind power
Solar power