1. Ecology Standards 6a. Know biodiversity is the sum total of different kinds of organisms & is affected by alterations of habitats 6b. Know how to analyze changes in an ecosystem resulting from changes in climate, human activity, introduction of non-native species, or changes in population size. 6c. Know how fluctuations in population size in an ecosystem are determined by the relative rates of birth, immigration, emigration & death. 6d. Know how water, carbon, & nitrogen cycle between abiotic & biotic resources and organic matter in the ecosystem & how oxygen cycles through photosynthesis & respiration. 6e. Know a vital part of an ecosystem is the stability of its producers and decomposers. 6f. Know at each link in a food web some energy is stored in newly made structures, but much energy is lost to the environment as heat, represented in an energy pyramid.

2. Ecosystem Structure

3. Passing of Energy All Energy starts from the sun Photosynthetic plants convert energy from the sun into food The energy moves through the ecosystem as one organism eats another

4. Autotrophs = Producers An organism that converts the sun’s energy into food

5. Heterotrophs = Consumers Organisms that obtain energy by eating other organisms Can eat plants or animals Or BOTH

6. Food Chains A model of the flow of energy through organisms in a community Flow of energy is shown by arrows

7. Transferred Energy At each step in the food chain only 10% energy is passed to the organism 90% of the energy is lost in the form of HEAT 90% HEAT 90% HEAT 90% HEAT

8. Trophic Level A step in the transfer of energy Producers are the 1 st trophic level ** they form the base of all food chains

9. Primary Consumers = Herbivores Feed directly on producers Make up the 2 nd trophic level

10. Secondary Consumers = Carnivores Eat only meat Feed on primary Make up the 3 rd

11. Omnivores Eat both producers and consumers

12. Scavengers Consumer that feeds on the tissue of dead animals

13. Decomposers (recyclers) Feed on wastes and dead organic matter from all trophic levels VERY IMPORTANT Waste would pile up without them to recycle it!

14. Ecological Pyramid Shows the relationship between producers & consumers in 3 ways: Biomass Energy # of organisms

15. Biomass Pyramid Biomass – mass of living organisms There is less biomass as you move up trophic levels

16. Energy Pyramid & 10% Law Only 10% of energy is passed to next level 1 st trophic level is important in determining the rest of the levels

17. # of organism pyramid Population of each trophic level decreases as you move up the trophic levels

18. Food Web Shows the interconnected food chains in a community or ecosystem A lot of food chains together