1. Energy Flow

2. Who eats what in an ecosystem?  Ecosystems are structured by who eats whom. A trophic level is the position that an organism occupies in a food chain- what it eats and what eats it. Every organism belongs to at least one feeding level or tropic level.

3. The trophic levels are:  Producers make their own food through photosynthesis or chemosynthesis Examples: grass, fern, cactus, flowering plant, tree, algae, some bacteria

4. Trophic Levels Cont.  Consumers get their energy by eating producers or other consumers. Examples: mouse, starfish, turtle, paramecium, sponge, ant, human

5. Trophic Levels Cont.  Decomposers break down dead organisms in an ecosystem and return the nutrients to soil, water and air. Converts bond energy from dead and decaying organisms into heat. Examples: fungus, bacteria, earthworms & insects earthworms & insects

6. Who can make their own food?  Autotroph auto means self troph means nourish troph means nourish  An organism that produce, or make their own food. Autotrophs are also called producers. (Plants & Algae)

7.  Heterotroph  An organism that obtain its energy by the consumption of other organisms.  Heterotrophs are also called consumers.

8. Types of consumers in an ecosystem  Primary Consumer – The first consumer in a food chain/food web and consumes a producer. Herbivores or plant eater  Secondary Consumer – The second consumer in a food chain/food web.  Tertiary Consumer – The third consumer in a food chain/food web. carnivore or omnivore

9. Organisms Are Grouped by What They Consume  Herbivore – An organism that eats plants, nuts, berries ie. rabbit, deer  Omnivore – An organism that eats plants and animals ie. black bear, human  Carnivore – An organism that eats animals ie. wolf, hawk, whale

10. Organisms Cont.  Scavenger – An organism that feeds off of dead animals that they did not hunt or kill themselves. ie. vulture  Decomposer – An organism which obtains its energy from dead or decaying organisms, thus returning nutrients into the soil ie. bacteria or fungi  Predator – An organism that feeds on what it hunts and kills ie. coyote

11.  Prey – An organism that is hunted and killed for food ie: mouse  Food Chain – A pathway in which energy flows through an ecosystem.  Food Web – All possible pathways in which energy flows through an ecosystem.

13. Energy flow… how it begins  Photosynthesis – Conversion of sun’s energy to food energy  6CO 2 + 6H 2 O + Sunlight energy  C 6 H 12 O 6 + 6O 2  (C 6 H 12 O 6 = food energy, chemical energy, potential energy - in bonds)

14. Energy flow…  Cellular respiration  Process by which chemical bonds (food energy) are converted to usable energy.  C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP (usable energy for cells)

15. Energy flow… how it begins  Photosynthesis – Conversion of sun’s energy to food energy  6CO 2 + 6H 2 O + Sunlight energy  C 6 H 12 O 6 + 6O 2  (C 6 H 12 O 6 = food energy, chemical energy, potential energy - in bonds)

16. Energy flow…  Cellular respiration  Process by which chemical bonds (food energy) are converted to usable energy.  C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP (usable energy for cells)