When talking about energy, organisms can be divided into 2 groups.

1. When talking about energy, organisms can be divided into 2 groups. • Autotrophs (producers) 2. Heterotrophs (consumers)

2. Autotrophsmake their own food by getting energy from the sun or chemicals Called “producers” because they produce their own energy.

3. There are 2 types of producers: • Photosynthesizers: use sunlight to make food 2. Chemosynthesizers: use chemicals to make food

4. Heterotrophs must eat things to get their energy. They cannot make energy on their own. Called “consumers” because they must consume other things to get energy

5. Types of consumers • Herbivores: feed on plants 2.Carnivores: feed on animals 3.Omnivores: feed on plants and animals

6. 4. Scavengers: feed on dead things 5. Decomposers : break down dead or decaying organisms and get nutrients out of the organism

7. The way energy is passed in an ecosystem is through the feeding system(different organisms eating each other)

8. The feeding systems in the ecosystems can be shown through a model called a food chain. A food chain is a simple model that shows the feeding relationship between several organisms. algae  tadpole  fish  blue heron The arrow always points towards the consumer (the eater) The arrow shows the direction of energy flow!

9. A food chain can be divided up into levels. These levels are called trophic levels. algae  tadpole  fish  blue heron 1st 2nd 3rd 4th

10. Each trophic level has a specific name. algae  tadpole  fish  blue heron 1st 2nd 3rd 4th a b c d • Producer • Primary consumer • Secondary consumer • Tertiary consumer

11. A food web is a more complex model that shows the connections of several food chains in an ecosystem.

12. Now that we know how to show the flow of energy through an ecosystem, how do we show the amount of energy that is being transferred from one organism to the next?

13. Ecological Pyramids!!! Ecological pyramids don’t just show the amount of energy that is transferred between each trophic level… They can also describe numbers and biomass at each trophic level.

14. Pyramid of Energy Only 10% of the available energy contained in one trophic level gets passed on to the next trophic level.

15. Where does the rest (90%) of the energy go? • Some energy is lost as heat. • Energy has already been used up by the captured food. • An entire trophic level cannot be consumed. • All the food is not eaten and digested.

16. Pyramid of Numbers Shows the relative number of organisms at each trophic level.

17. Pyramid of Biomass Total amount of living matter within each trophic level. Represents the amount of potential food available for each trophic level in an ecosystem!