1. What Is Life? 8 Life Characteristics ______________________________________________________

2. Ecology The study of the interaction of living things with ______________________________________________________ From Greek “oikos” – a place to live “logos” - study

3. Energy pyramid On average only ______ of energy at one trophic level is available to the next

5. Biotic factors of an ecosystem Population All the members of the ________________ that inhabit a particular area Community All of the members of ___________________ Ecosystem ________________ and ________________ factors

6. Abiotic Factors ( components) Ex. Biotic Factors ( components) Ex.

7. Biosphere All of Earth’s __________________________ Lithosphere - Hydrosphere - Atmosphere -

8. Biome Characteristics Composed of __________________. Certain plant & animal _____________. Have specific __________ with similar plants and animal ________________.

9. Categories of Biomes Tundra Taiga Grasslands Deserts Deciduous Forests Tropical Rainforests Other Biomes Chaparral Savanna Tropical Deciduous Rain Forest

11. Biomes of the world

12. Soil nutrients Simple Food chain

13. Categories of Biotic Organisms Producer Consumer - in most ecosystems -phytoplankton (, ) - synthesis or synthesis 6CO 2 + 6H 2 O → C 6 H 12 O 6 + 6O 2

14. Decomposers -external digestion -mostly bacteria and fungi -feed on partially decomposed matter -e.g. crabs, termites, worms -e.g. vultures, crows, lobsters

15. Consumers -feed on producers or consumers -plant eaters -primary consumers -meat eaters -secondary (tertiary) consumers -eat both plants and animals

16. Food Chains all organisms feeding at a particular level

17. ______________– a summary of the feeding relationships in a community

19. Trophic level – position in the ________________ –___________(lowest level) –____________– act as predators and prey –______ predators – have no predators

21. _____________________________________– one that has a dominant effect on community composition –reduce _______________among prey species –allow poorer competitors to persist Top predators __________always keystone predators –abundance –feeding patterns

22. Stability in Food Webs A community is stable if –it doesn’t change much in response to environmental changes, or –it returns to its previous state after a disturbance Early models suggested that larger food webs are unstable

23. Current view: more diverse food webs are more stable –more species = weaker interactions on average –species influenced by many weak interactions have more stable populations than species with few strong interactions –This is why elimination of species is dangerous! Field research suggests most interactions in nature are weak.

24. No predators Limited only by food Limited by predation Limited by competition and resources