1. Food Chains, Webs, and Pyramids

2. Ecosystems are divided into different sections called trophic levels Each trophic level represents a transfer of energy. –For Example, energy is transferred from the prey to the predator

3. Trophic Levels Producers: Organisms that create energy in an ecosystem –Most fundamental trophic level –Absorb energy from the sun and convert it into chemical energy by photosynthesis –Usually plants and algae

4. Consumers: Organisms that can’t produce their own energy –Energy comes from producers –Different types of consumers:

5. Primary Consumers: eat producers (plants) for energy (herbivores) Secondary Cosumers: feed on primary consumers (carnivores or omnivores) Tertiary Consumers: feed on secondary consumers (carnivores or omnivores)

6. Decomposers: get energy by breaking down the dead remains of other living things –Includes some bacteria, fungi, and insects

7. Demonstrating Energy Changes Food Chain: simple diagram of how energy flows. –Arrow points to organism gaining energy (the one that is eating) –EXAMPLE: –Grass  rabbit  snake  hawk

8. Food Web Food Web: Shows a network of connected food chains

9. Food Web

10. Energy Pyramid The flow of energy creates an energy pyramid –Each level of the pyramid uses energy less efficiently than the previous level.