1. Food Chains, Food Webs and Energy Pyramids
Ecology 6.f
Chapter 22

2. The Food Chain…

3. Transfer of Energy In a food chain:
Energy is passed from one link to another

4. When a herbivore eats…
Only a fraction of the energy is passed from one link of the food chain to the next.

5. “Or shall we say dissipated into the environment as heat.”
Most of the Energy is…
L O S T
“Or shall we say dissipated into the environment as heat.”

6. Or used up through…
Reproduction
Movement
Digestion

7. Therefore, when a herbivore…

8. is eaten by a carnivore…

9. only a small amount of energy passes.

10. This dissipation of energy…
Is represented in energy pyramids.

11. So why do they call it an Energy Pyramid?

12. What might go here?
? ? ? ?

13. What might go here?

14. Examples

15. Desert

16. Coniferous Forest

17. Deciduous Forest

18. Temperate Forest

19. Fluctuations in Populations
Ecology 6 b & c
Chapter 20

20. What might change a population?
Birth Rate
Immigration
Emigration
Death Rate

21. Birth Rate
Number of births occurring in a period of time.

22. Immigration
The movement of individuals into a population.

23. Emigration
Movement of individuals out of a population.

24. Death Rate or Mortality Rate
Number of deaths in a period of time.

25. What factors might change an ecosystem?

26. Changes in Ecosystems Population Size Climate Human Activity
Introduction of Nonnative Species