Zebra mussels threaten the Great Lakes ecosystem. They compete with fish for plankton and clarify the water, causing increased plant growth. Ecosystems are complex systems consisting of living organisms like plants, animals, bacteria, and viruses interacting with non-living components like sunlight, water, and minerals. The role an organism plays and the resources it uses in an ecosystem is known as its niche. Ecosystems normally exist in a steady state or homeostasis before being disrupted by events like fires, hurricanes, or human activity.

2. Zebra mussels are a great threat to the Great Lakes. Compete with fish for plankton Clarify water, cause plants to grow

3. The soil, air, and surface where living things can grow

4. Organism Human being Population Family Community Town Ecosystem People and buildings Biome State of PA/US Biosphere World/Planet

5. Large habitat Atlantic Ocean Forests Jungles Small habitat – “microhabitat” Rotting Log Large Intestine Riffle, Run, or Pool in a Stream

6. Living components of an ecosystem Competing trees Predators Viruses Bacteria Pathogens

7. Non-living components in an ecosystem Sunlight Air Water Minerals

9. Much more complex Represent actuality

10. Any given environment can only support so many organisms If a population reaches its max, organisms will: Die Move Adapt

11. Eventually the environment will no longer support any more individuals The graph is in the shape of an S: “S-Curve”

12. The role an organism plays in an ecosystem Two organisms CANNOT occupy the same niche If they did, they would compete for resources Die Move Adapt

13. Homeo = Same, Stasis = State of activity A “steady state” that an ecosystem is normally in before a disruption

14. Fire Tornado Volcano Humans Hurricanes Tsunami

15. Geographic areas with similar soil and climates Have similar species adaptations Common plants and animals characteristic of those climates

16. Forests Tropical Rain Forests Deciduous and Scrub Forests Temperate Deciduous Temperate Coniferous Boreal Forest

17. Savanna Temperate Grassland Tundra Desert Chaparral

18. Mountains Ice Cap Freshwater Marine

19. The Water Cycle Precipitation Evaporation Transpiration Condensation Run-off/Groundwater

20. Atmospheric CO 2 Photosynthesis Animals eat plants Respiration Plants form coal Humans burn Fossil Fuels

21. Atmospheric N 2 Nitrogen Fixation Plant uptake Animals/Decomposition

22. The change in plant and animal species over time Primary Secondary

23. Only occurs on recently formed land Hawaiian Islands Ice Caps Plate Boundaries Pioneer Species First species to establish themselves Climax Community The final stage of succession

24. Occurs after a disturbance Fire Volcano Pioneer Species First species to establish themselves Climax Community The final stage of succession