1. Energy in Ecosystems
Organisms interact in order to obtain energy and resources necessary to survive.

2. Autotrophs Organisms that make their own food. Auto = self
Also called Producers

3. Heterotrophs Depend on other organisms for food and energy.
Hetero = other
Also called consumers

4. 5 Types of Heterotrophs

5. Herbivores
Eat only plants/autotrophs

6. Carnivores
Eat other heterotrophs

7. Scavengers/Detrivores
Consume organisms that are already dead

8. Omnivores
Eat both animals and plants
omni = all

9. Detritivores/ Decomposers
Absorb nutrients from dead organisms; break down decaying matter
Fungus, Bacteria

10. Quick Review

11. 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

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

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

14. FOOD CHAIN

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

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

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

21. What’s wrong with this food web?

22. How do Toxic Chemicals Affect Food Chains & Food Webs?

23. Toxic Chemicals
Nonbiodegradable materials CANNOT be broken down, remain in environment indefinitely

24. Toxic Chemicals
Biological magnification concentration of harmful nonbiodegradable substance increases in organisms as move up food chain

25. Biomagnification of DDT Video

26. Ecology 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

27. Pyramid of energy
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

29. Pyramid of numbers
Based on the number of individual organisms at each trophic level
Pyramid of Numbers
Fox (1)
Birds (25)
Grasshoppers (250)
Grasses (3000)

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

32. Energy Transfer and Tropic Levels Video