1. How Ecosystems Work Homework: Chapter 5: Read Pages 117-123
Define Key Terms (pg. 117):
Photosynthesis
Producer
Consumer
Decomposer
Cellular Respiration
Food Chain
Food Web
Trophic Level

2. Hierarchy of Life Simple  Complex Atom Molecule Organelle Cell Tissue
Body System
Organism
Population
Community
Ecosystem

3. ACTIVITY: What’s the story?

4. First Principle of Ecology
Interconnectedness

5. Ecological Concepts
The way organisms interact w/ each other and w/ nonliving surroundings.

6. Ecosystem
A group of plants, animals and microbes interacting with each other and the physical environment in a sustainable way.

7. How big is an ecosystem?

8. Types of Ecosystems

9. Biomes: large terrestrial ecosystems

10. Biosphere
Earth’s “super ecosystem” includes all life forms and the physical environments supporting life.
Includes: air, land, surface rocks, and water w/in which life occurs, and which biotic processes take place!

11. Ecological Concepts

12. Ecological Concepts Limiting Factors
Factors that are critical to a species’ success.
Abiotic or Biotic

13. Range of Tolerance Trout Black Bass
Live in fast flowing, cold water
More dissolved oxygen
Black Bass
Adapted to lower oxygen concentrations and higher water temperatures
Limiting Factors: water temperature and dissolved oxygen

14. Ecological Concepts Habitat and Niche Habitat Niche Ex: Beaver
Space organism lives
(its address)
Niche
Functional role it has in its surroundings
(its profession)
Ex: Beaver
Flooding, kills trees, enhances environment for other animals, and is a food source for predators.

15. Categories of Organisms (common to every ecosystem)
Autotrophs (producers)
Self-feeding
Typically, green plants

16. Categories of Organisms (common to every ecosystem)
Heterotrophs
Consumers
Must eat others
5 Types:
Herbivores
Carnivores
Omnivores
Decomposers (bacteria and fungi)
Detritus Feeders (scavengers)

17. Feeding Relationships
Predator-prey
One organism kills and eats another
Grazing
Herbivore-producer
Host-Parasite
Parasite lives in host to derive nourishment.
Host is generally harmed, but not killed immediately.

18. Energy Flow Through Ecosystem
Food Chains
Show direction of energy flow b/w organisms in an ecosystem
Bioaccumulation: build up of toxins in the food chain.

19. Energy Flow Through Ecosystem
Food Web
Shows all possible pathways

20. Energy Flow Through Ecosystem Trophic Levels

21. Biomass Pyramid

22. Biomass Pyramid Continued
Shows the relative proportions of biomass at each trophic level.
In most efficient ecosystems, there is only about 10% of food energy available for the next higher trophic level– what happened to the other 90%?
Food chains in most terrestrial ecosystems rarely go higher than 4 trophic levels.

23. Activity