1. Energy Flow

2. Warm Up
How does energy and matter flow through living systems? (Hint : Think about the laboratory.)

3. Lecture 2: Energy Flow in Ecosystems

4. Feeding Relationships
Energy flow through an ecosystem in one direction:
Sun or inorganic compounds autotrophs (producers)
Various heterotrophs (consumers) decomposers
The relationships between producers and consumers connect organisms into feeding networks based on who eats whom.

5. Feeding Relationships
Food Chains: a series of steps in which organisms transfer energy by eating and being eaten.

6. Feeding Relationships
Food Webs: links all the food chains in an ecosystem together.

7. Feeding Relationships
Trophic level: Each step in a food chain or food web. Each consumer depends on the trophic level below it for energy. 1st=Producers 2nd, 3rd, or higher=Consumers

8. Ecological Pyramids
Ecological Pyramids: diagram that shows the relative amounts of energy or matter in each trophic level of a food chain web.

9. Types of Ecological Pyramids
1. Energy Pyramid 2. Biomass Pyramid 3. Pyramid of Numbers

10. Ecological Pyramids
Energy Pyramid: shows the relative amount of energy available at each trophic level.
Only 10% of the energy is transferred to organisms at the next trophic level.

11. Ecological Pyramids
2. Biomass Pyramid: Represents the amount of living organic matter at each trophic level.
Largest biomass is at the base of the pyramid.

12. Ecological Pyramids
3. Pyramid of Numbers: shows the relative number of individual organisms at each trophic level.

13. Summarize your lecture notes
Create a summary of what you learned in your own words.