Interdependence: A Key Theme in Ecology

1. Section 1 Introduction to Ecology Chapter 18 Interdependence: A Key Theme in Ecology • Organisms and Their Environments • Species interact with both other species and their nonliving environment. • Interdependence is a theme in ecology—one change can affect all species in an ecosystem.

2. Section 1 Introduction to Ecology Chapter 18 Making an Ecosystem Model

3. Section 1 Introduction to Ecology Chapter 18 Levels of Organization • Ecologists recognize a hierarchy of organization in the environment: biosphere, ecosystem, community, population, and organism.

4. Section 1 Introduction to Ecology Chapter 18 Levels of Organization

5. Section 1 Introduction to Ecology Chapter 18 Levels of Organization, continued • The Biosphere • The broadest, most inclusive level of organization is thebiosphere,the volume of Earth and its atmosphere that supports life.

6. Section 1 Introduction to Ecology Chapter 18 Levels of Organization, continued • Ecosystems • The biosphere is composed of smaller units called ecosystems. • An ecosystemincludes all of the organisms and the nonliving environment found in a particular place.

7. Section 1 Introduction to Ecology Chapter 18 Levels of Organization, continued • Communities, Populations, and Organisms • Acommunityis all the interacting organisms living in an area. • Below the community level of organization is thepopulationlevel,where the focus is on the individual organisms of a single species.

8. Section 2 Ecology of Organisms Chapter 18 Ecosystem Components • Biotic and Abiotic Factors • Bothbiotic, or living, factors andabiotic, or nonliving, factors influence organisms. Examples of abiotic factors are climate, sunlight, and pH. • https://www.youtube.com/watch?v=E1pp_7-yTN4

9. Section 2 Ecology of Organisms Chapter 18 Organisms in a Changing Environment • Acclimation • Some organisms can adjust their tolerance to abiotic factors through the process ofacclimation.

10. Section 2 Ecology of Organisms Chapter 18 Organisms in a Changing Environment, continued • Control of Internal Conditions • Conformers are organisms that do not regulate their internal conditions; they change as their external environment changes. • Regulators use energy to control some of their internal conditions.

11. Section 2 Ecology of Organisms Chapter 18 Organisms in a Changing Environment, continued • Escape from Unsuitable Conditions • Some species survive unfavorable environmental conditions by becoming dormant or by migrating.

12. Section 2 Ecology of Organisms Chapter 18 The Niche • A nicheis a way of life, or a role in an ecosystem.

13. Section 3 Energy Transfer Chapter 18 Producers • Most producersare photosynthetic and make carbohydrates by using energy from the sun.

14. Section 3 Energy Transfer Chapter 18 Consumers • Consumersobtain energy by eating other organisms and include herbivores, omnivores, carnivores, detritivores, and decomposers.

15. Section 3 Energy Transfer Chapter 18 Energy Flow • Food Chains and Food Webs • A single pathway of energy transfer is afood chain. • A network showing all paths of energy transfer is a food web.

16. Section 3 Energy Transfer Chapter 18 Food Chain in an Antarctic Ecosystem

17. Section 3 Energy Transfer Chapter 18 Food Web in an Antarctic Ecosystem

18. Section 3 Energy Transfer Chapter 18 Energy Flow, continued • Energy Transfer • Ecosystems contain only a few trophic levels because there is a low rate of energy transfer between each level. • https://www.youtube.com/watch?v=0glkXIj1DgE • https://www.youtube.com/watch?v=ScizkxMlEOM

19. Section 3 Energy Transfer Chapter 18 Energy Transfer Through Trophic Levels

20. Section 4 Ecosystem Recycling Chapter 18 The Water Cycle • Key processes in thewatercycleare evaporation, transpiration, and precipitation. • https://www.youtube.com/watch?v=al-do-HGuIk

21. Section 4 Ecosystem Recycling Chapter 18 Water Cycle

22. Section 4 Ecosystem Recycling Chapter 18 The Carbon Cycle • Photosynthesis and cellular respiration are the two main steps in thecarbon cycle. • https://www.youtube.com/watch?v=4vJ_1ojjlxw

23. Section 4 Ecosystem Recycling Chapter 18 Carbon Cycle

24. Section 4 Ecosystem Recycling Chapter 18 Nitrogen Cycle • Nitrogen-fixing bacteriaare important in thenitrogen cyclebecause they change nitrogen gas into a usable form of nitrogen for plants. • https://www.youtube.com/watch?v=oy8e2HrOh6Q

25. Section 4 Ecosystem Recycling Chapter 18 Nitrogen Cycle

26. Section 4 Ecosystem Recycling Chapter 18 Phosphorus Cycle • In thephosphorus cycle,phosphorus moves from phosphate deposited in rock, to the soil, to living organisms, and finally to the ocean.