1. Energy in Ecosystems Food Chains and Webs
Note: Organisms interact in order to obtain energy and resources necessary to stay alive.

2. Energy Flow Energy flows thru an ecosystem in one direction:
sun autotroph heterotroph

3. Autotrophs Organisms that use solar energy to make their own food.
Auto = self
Also called Producers

4. Heterotrophs
Organisms that depend on other organisms for food and energy.
Hetero = other
Also called consumers

5. 5 Types of Heterotrophs

6. Herbivores
Eat only plants

7. Carnivores
Eat other heterotrophs or eat meat

8. Scavengers
Eat organisms that are already dead

9. Omnivores
Eat both animals and plants
omni = all

10. Decomposers
Absorb nutrients from dead organisms
Fungi, Bacteria

11. Quick Review

12. What do you call an organism that can make its own food?
What direction does energy flow thru an ecosystem?
What do you call an organism that eats both animals and plants?
What do you call an organism that absorbs nutrients from dead organisms?
autotroph
Producer  consumer
omnivore
detrivore

13. Food Chain
A model that shows how matter and energy move through an ecosystem. It has arrows that show the direction that energy is being transferred.

14. FOOD CHAIN

15. Trophic Level
A feeding step in a food chain that represents each organism.

16. Can you name the trophic levels below??
Tertiary consumer
Primary consumer
Producer
Secondary consumer

18. Food Web
Shows all the possible feeding relationships at each trophic level in a community.

20. Energy pyramids
Diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web.
3 types

21. Pyramid of energy
Heat
0.1% Consumers
1% Consumers
10% Consumers
100% Producers
Parasites, scavengers, and decomposers feed at each level.
Only about 10% of energy available within one trophic level is transferred to organisms at the next trophic level

23. Pyramid of numbers
Pyramid of Numbers
Fox (1)
Birds (10)
Grasshoppers (100)
Grasses (1000)
Based on the number of individual organisms at each trophic level

24. Pyramid of Biomass
The total amount of living tissue within a given trophic level is called biomass.
A pyramid of biomass represents the amount of potential food available for each trophic level in an ecosystem.