1. Introduction to Ecosystems 2/13/12

2. What is a species?  A group of individuals who have similar enough DNA that they are able to produce viable offspring.

3. What is a population?  Several individuals of the same species that live in the same area.

4. What is a community?  Populations that interact with one another.

5. What is an ecosystem?  An ecosystem a community of biotic (living) organisms that interact with abiotic (non-living) organisms in an interdependent system.

7. What is a biome?  A type of ecosystem that shares similar climate, and components.

8. What are primary producers?  An Autotroph; A species that creates its own food through photosynthesis or from reduced inorganic compounds.

9. What are consumers?  Organisms that eat other organisms to obtain energy.

10. What are decomposers?  Organisms that obtain energy by feeding on the dead remains of other organisms or waste products.  Get nutrients and live on dead organic matter (habitat)

11. What is are trophic levels?  Trophic levels are organisms that obtain their energy from the same source.  Energy moves through ecosystems in the form of light, or chemical energy.  Usually no more than 4-5 trophic levels, due to 2 nd law of Thermodynamics.

12. What is an herbivore?  An organism that eats plants.

13. What is an omnivore?  An organism that eats plants and animals.

14. What is a carnivore?  An organism that eats other animals.

15. What is a predator?  An organism that kills and consumes other organisms.

16. What is a prey?  An organism that is consumed by a predator.

17. What is the carrying capacity of a population?  When a population stabilizes at a maximum number of individuals that can be supported by resources available in the habitat over a sustained period of time.

18. How does the carbon cycle relate to the food chain?  Carbon (and other nutrients) move up the food chain, carrying with it stored energy.

19. What is parasitism?  A long term relationship between two organisms that is beneficial to one organism (the parasite), but detrimental to the other (the host).  (+/-)  Example: Wasps that lay eggs in caterpillars, malaria causing plasmodium, misquitos, Mycobacterium (causes tuberculosis), lice, tapeworms

20. What is mutualism?  A type of symbiotic relationship between two species that is beneficial to both species.  (+/+)  Examples: Bees and flowers, Treehoppers and ants, Lichen = algae+fungus

21. What is commensalism?  A relationship in which one organism benefits and one the other neither benefits or is harmed by the interaction.  (0/+)  Barnacles on whales, Remora sharks hitch a ride on larger sharks, clown fish and sea anemones

22. What is amensalism?  A relationship in which one organism is harmed and the other neither benefits or is harmed.  (0/-)  Penecillin kills bread mold, humans and cattle or sheep trample the grass, Black walnut trees secrete chemicals that kill other plants, redwoods have tannic acid in their leaves/needles that make the soil too acidic for other plants to grow

23. What is competition?  A relationship in which both species are negatively affect by the outcome of the interaction.  (-/-)

24. What is an ecological niche?  A specific role or job that an individual has in an ecosystem.

25. What is a keystone species?  A species that has an exceptionally great impact on the surrounding community.  Pisaster (sea star), sea otter

26. Net Primary Productivity

27. What is photosynthesis?  A series of chemical reactions and electron transfer events that converts the energy of light into chemical energy stored in glucose.  Equation for photosynthesis: 6CO 2 + 6H 2 0 + light energy  C 6 H 12 O 6 +6O 2

28. Why is dissolved oxygen a measure of productivity?  Dissolved oxygen is produced in photosynthesis.  Dissolved oxygen is consumed in cellular respiration.

29. What is gross primary productivity?  The amount of biomass produced by photosynthesis per unit area over a specific time period.

30. What is Respiration?  Metabolizing glucose (carbon compound) into chemical energy using oxygen.

31. What is Net primary productivity?  The Net primary productivity= gross primary productivity - respiration