1. Food Chains And Food Webs Principles of Ecology KEY CONCEPT Ecology is the study of the relationships among organisms and their environment.

2. Food Chains And Food Webs Principles of Ecology Interdependence: A key theme in Ecology Species interact with both other species and their nonliving environment One change can affect all species in an ecosystem

3. Food Chains And Food Webs Principles of Ecology Ecologists study environments at different levels of organization. - each level has unique properties resulting from interactions with its components

4. Food Chains And Food Webs Principles of Ecology Organism An organism is an individual living thing, such as an alligator.

5. Food Chains And Food Webs Principles of Ecology Organism Population A population is a group of the same species that lives in one area.

6. Food Chains And Food Webs Principles of Ecology Organism Population Community A community is a group of different species that live together in one area.

7. Food Chains And Food Webs Principles of Ecology Organism Population Community Ecosystem An ecosystem includes all of the organisms as well as the climate, soil, water, rocks and other nonliving things in a given area.

8. Food Chains And Food Webs Principles of Ecology Organism Population Community Ecosystem Biome A biome is a major regional or global community of organisms characterized by the climate conditions and plant communities that thrive there.

9. Food Chains And Food Webs Principles of Ecology The Biosphere The broadest, most inclusive level of organization is the biosphere, the volume of Earth and its atmosphere that supports life.

10. Organisms and Their Environment KEY CONCEPT Every ecosystem includes both living and nonliving factors.

11. Organisms and Their Environment An ecosystem includes both biotic and abiotic factors. Biotic factors are living things. –plants –animals –fungi –bacteria plants

12. Organisms and Their Environment Abiotic factors are nonliving things. –moisture –temperature –wind –sunlight –soil moisture sunlight

13. Organisms and Their Environment Organisms in a Changing Environment Acclimation –Some organisms can adjust their tolerance to abiotic factors through the process of acclimation. –Occurs within the lifetime of an individual organism Adaptation –Genetic change in a species or population that occurs from generation to generation over time

14. Organisms and Their Environment Organisms in a Changing Environment Control of Internal Conditions –Conformers Organisms that do not regulate their internal condtions; they change as their external environment changes –Regulators Use energy to control some of their internal conditions

15. Organisms and Their Environment Organisms in a Changing Environment Escape from Unsuitable Conditions –Some species survive unfavorable environmental conditions by becoming dormant or migrating.

16. Organisms and Their Environment Changing one factor in an ecosystem can affect many other factors. Biodiversity is the assortment, or variety, of living things in an ecosystem. Rain forests have more biodiversity than other locations in the world, but are threatened by human activities.

17. Organisms and Their Environment A keystone species is a species that has an unusually large effect on its ecosystem. keystone

18. Organisms and Their Environment Keystone species form and maintain a complex web of life. creation of wetland ecosystem increased waterfowl Population increased fish population nesting sites for birds keystone species

19. Organisms and Their Environment The Niche A niche is a way of life, or role in an ecosystem –Range of conditions a species can tolerate –Resources it uses –Methods by which it obtains resources –Number of offspring –Time of reproduction –All other interactions with its environment