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

2. Objectives
I can identify and name trophic levels with food chain & web examples
I can identify 5 types of consumers
I understand how energy in an ecosystem is measured and ‘flows’
I can explain why ecosystems are represented by pyramids

3. Energy Flow Energy flows through an ecosystem in one direction:
sun autotroph heterotroph

4. Autotrophs Organisms that make their own food. Auto = self
Aka: Producers

5. Heterotrophs Depend on other organisms for food and energy.
Hetero = other
Aka: consumers

6. 5 Types of Heterotrophs

7. Herbivores
Eat only plants

8. Carnivores
Eat other heterotrophs

9. Scavengers
Eat organisms that are already dead

10. Omnivores
Eat both animals and plants
omni = all

11. Decomposers
Absorb nutrients from dead organisms
Fungi, Bacteria

12. Quick Review

13. 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
decomposer

14. 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.

15. 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.

20. Decomposers recycle nutrients – waste and dead organisms

21. Learning Check

22. 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

23. 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
Kcal, J

25. 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)

26. Pyramid of Biomass
The total amount of living tissue within a given trophic level is called biomass.