1. Communities Using Energy

2. Energy Flow

3. Pass it Along
Energy flows in one direction through an ecosystem, from the sun or inorganic compounds to producers (organisms that can make their own food) through various levels to consumers (organisms that rely on other organisms for food). Your body gets the energy and materials it needs for growth and repair from the foods you eat.

4. Energy Flow

5. Using Energy
all living things in a community use ATP as a source of energy
living things differ on what FOOD they use to MAKE the ATP and how they OBTAIN that food

6. Autotrophs
organisms that use energy from their environment to make simple inorganic compounds into complex organic compounds (food)
a.k.a. producers
produce energy through photosynthesis or chemosynthesis

7. Photosynthesis a common process of using light energy to create food
most of the life on earth can trace its energy source to photosynthesis

8. Chemosynthesis
an uncommon process of obtaining energy from inorganic chemical compounds
occurs in areas that receive little-to-no sunshine
ocean bottoms, caves

9. Heterotrophs organisms that rely on other organisms for their energy
a.k.a. consumers

10. Heterotrophs Fall into 4 categories (with 1 major subcategory)
Herbivores
Carnivores
Omnivores
Detritivores
Decomposers

11. Herbivores
organisms that eat plants
Examples: cows, koalas, pandas

12. Carnivores
organisms that eat meat
Examples: wolves, lions, anteaters

13. Omnivores organisms that eat both plants and animals
Example: bears, humans

14. Detritovores
an organism that relies upon other dead or decaying organism for its energy (food) source
Examples: vultures, worms, bacteria, fungi

15. Decomposers a subcategory of detritovores
are able to breakdown substances into those that producers/autotrophs can convert into life's molecules
take dead material and break it down into the simplest molecules
Examples: worms, bacteria, fungi

16. Energy Flow
all organisms are connected by the flow of energy and matter
these connections are illustrated by food chains and food webs
organisms are represented by names or pictures
direction of transfers of energy and/or matter is represented by arrows

17. Food Chains vs. Food Webs
show the one way flow of energy as it is passed from an autotroph (producer) to various heterotrophs (consumers)
Food webs
links all of the food chains in an ecosystem together

18. Food Web vs. Food Chain

19. Food Web – What about when an organism in the web dies?

20. Trophic Levels
all the organisms at a trophic level are the same number of steps away from initial source of energy of the system
the source of energy for most ecosystems is the sun
autotrophs (producers) are closest to the source of energy and are the first trophic level

21. Holt Biology, Fig. 47-5, p.846