1. What happens to energy as you go up a food chain?
February 9, 2010
What is a food chain?
What happens to energy as you go up a food chain?

2. Q: Let’s turn our focus to ecosystems
Q: Let’s turn our focus to ecosystems. What are some interactions of ecosystems?
Habitat: where organisms live
Niche: an organism’s role in the ecosystem
Is it an herbivore, omnivore, carnivore?
Is it a predator?
Where does it live (in trees, water, on ground, etc)?
Is it food for other organisms?

3. Q: How does energy flow in an ecosystem?
It always starts with the SUN. (most energy available)

4. Q: How does energy flow in an ecosystem?
Autotroph: makes their own food using sunlight (PLANTS) or chemicals (some bacteria-picture below), also called PRODUCERS
“Auto” = self
“troph” = feed

5. Q: How does energy flow in an ecosystem?
Heterotroph: eats other stuff
“hetero” = different/other
“troph” = feed
Can be called consumers

6. Q: How does energy flow in an ecosystem?
Herbivores: eat only plants
Carnivores: eat other heterotrophs (animals)
Omnivores: eat plants and animals
Detritivores: animal that eats dead things and return nutrients to soil
Decomposers: bacteria or fungi that secrete chemical to break down matter and absorb nutrients, return nutrients to soil

7. Q: How can we show energy flow in an ecosystem?
Energy is “lost” as we move through an ecosystem (HEAT!)
Food chains
Simplified version
Use arrows to show flow of energy

9. Q: How can we show energy flow in an ecosystem?
Food Webs
Many food chains put together
Use arrows to show flow of energy
***Trophic Level: each step of a food chain/web/pyramid***
For example: Producers are one trophic level, the next are primary consumers, then secondary consumers, etc.

10. Q: How can we show energy flow in an ecosystem?
Ecological Pyramids
Pyramid of Energy: represents energy available at each trophic level

11. Q: How can we show energy flow in an ecosystem?
90% of energy is lost each time you move a step
If you start with 100 J of energy in producers:
primary consumers will get 10 J
secondary consumers will get 1 J
tertiary consumers will get 0.1 J.

12. Q: How can we show energy flow in an ecosystem?
Pyramid of Biomass: each level represents amount of biomass consumed by next trophic level
Biomass: total mass of living matter at each trophic level

14. Q: How can we show energy flow in an ecosystem?
Pyramid of Numbers: each level represents number of organisms consumed by the next trophic level

15. Homework Complete part 5 of HW pkt
Complete Food Chain activity from MONDAY (Go With the Flow… the Energy Flow)
Complete yesterday’s assignments
Picture of all three cycles combined (COLORED)
Parts 6 & 7 of packet
Work on review (due FRIDAY)
Make sure you pick this up from the side table!!!!