3. Ecology  Ecology - the study of relationships between organisms and their environment.  How the environment determines what organisms live in an ecosystem  How organisms affect the environment.  How organisms interact with each other.

4. Careers EmployersExamples of available work  Federal, state, and local government agencies  EPA  DEP  Universities  Environmental consulting firms  Forestry  Land use planning  Waste management  Fish and Game commission  Environmental law  Research  Many others

5. Terms:  Biosphere – the area of the earth where life exists.  most life exists within a few meters of the earth’s surface  contains ecosystems  Ecosystem – ecological unit that contains all of the interacting parts of an environment  biotic factors – living components  abiotic factors – nonliving components

8. http://www.paherps.com/herps/frogs-toads

9. ://www.paherps.com/herps/snakes

10. http://www.paherps.com/herps/turtles

11. http://www.batmanagement.com/B atcentral/batspecs.html

32. Trophic level – feeding level

33. Primary Producers  Autotrophs – make their own food  Include plants, algae, and photosynthetic bacteria.

34. Primary Consumers  Also called first level consumers  Eat producers  Herbivores

35. Secondary consumers  Also called second level consumers  Eat primary consumers  Carnivores can be secondary consumers

36. Tertiary consumers  Also called third level consumers  Carnivores can be tertiary consumers

37. Related Terms  Omnivores – eath both producers and consumers.

38. Teeth of different trophic levels

39. Related terms  Scavengers – feed on organisms that have recently died.

40. Related terms  Decomposer – break down dead tissues and wastes into nitrogen, carbon, phosphorus, and other elements and compounds.

41. Food chain  Specific order in which organisms obtain energy from in an ecosystem.

42. Food web  Shows feeding relationships of an entire ecosystem.  Shows how food chains in an ecosystem overlap.

44. Ecological Pyramids The amount of available energy, numbers of organisms, and amount of biomass change with trophic level. Energy pyramid – the amount of available energy decreases with trophic level.  Most of the energy in an ecosystem is locked up in producers.  This is because the transfer of energy from one trophic level to the next is not complete.

46. Numbers pyramid  Most numbers pyramids resemble energy pyramids.  As trophic levels increase numbers of organisms usually decrease.

47. Brd bird  There are times when the numbers pyramid is not followed. o Ex. One large tree may support thousands of caterpillars.

48. Biomass Pyramid  Biomass- the total dry weight of the organisms in the ecosystem.  Follow both regular and inverted pyramid forms.