Ecology- background

1. Ecology- background By PresenterMedia.com Unit 2

2. I. Ecology Ecology: study of relationships among living organisms and interactions organisms have with the environment Ecologists observe, experiment, and model using a variety of tools and methods.

3. II. The Biosphere Biosphere: a thin layer around the earth • Extends several kilometers above earths surface • Extends several kilometers below Earth’s surface

4. II. The Biosphere

5. III. Biotic and Abiotic factors Biotic factor • Living factors in an organism’s environment Abiotic Factor • Nonliving factors in an organism’s environment

6. IV. Levels of Organization • Organ systems • Organism/Species • Multicellular organisms • Population • Community • Ecosystem • Biome • Biosphere • Subatomic particles • Atom • Molecule • Organelle • Cell • Unicellular organisms • Tissue • Organs

7. V. Ecosystem Interactions Habitat • Area where an organism lives Niche • The role or position an organism has in its environment.

8. VI. Community Interactions Competition • More than one organism uses a resource at the same time Predation • Get food/energy by eating other organisms.

9. VII. Symbiotic Relationships Symbiotic Relationships • Close relationship that exists when two or more species live together • Mutualism • both benefit • Commensalism • one benefits; other no harm or benefit • Parasitism • host is killed

10. In what type of activity would you most expect an ecologist to be involved? identifying and classifying various species of insects in an ecosystem locating fossils of distinct species of turtles in a geographical area observing the relationships that woodpeckers have with other species in their environment studying the internal organs of a seal to learn how it survives in its environment Answer: C

11. Which are biotic factors in a forest environment? plants and microscopic organisms living in the soil pH and salt concentration of the soil sunlight, soil type and soil nutrients temperature, air currents and rainfall Answer: A

12. The act of one organism consuming another organism for food is _______. predation Parasitism Commensalism Mutualism Answer: A

13. Certain types of tropical orchids use trees for support in order to grow higher and obtain more light. This neither harms nor benefits the tree. What type of symbiotic relationship is this? Commensalism Competition Mutualism Parasitism Answer: A

14. What is the name for a group of interacting populations that occupy the same area at the same time? Ecosystem Habitat Biological community Biotic collection Answer: C

15. Section 2.3 Cycling of Matter I. Cycles in the Biosphere Energy is transformed into usable forms to support the functions of an ecosystem. The cycling of nutrients • Matter in living organisms • Physical processes found in the environment like weathering

16. II. Biogeochemical cycles The exchange of matter through the biosphere Bio= life Geo= earth Chemical= chemistry

17. III. The Water Cycle

18. III. Water Cycle About 90% of water vapor evaporates from oceans, lakes, and rivers About 10% evaporates from the surface of plants through transpiration. Freshwater • Constitutes about 3% of all water on Earth • About 69% of all freshwater found in ice caps and glaciers

19. IV. Carbon and Oxygen Cycles

20. IV. Carbon and Oxygen Cycles Carbon and oxygen often make up molecules essential for life Carbon and oxygen recycle relatively quickly through living organisms

21. V. Terms of Cycles Long-term Cycle • Organic matter converted to peat, coal, oil, or gas deposits (carbon) • Calcium carbonate (carbon and oxygen) Sort-term Cycle • Burning fossil fuels (carbon)

22. I. The Nitrogen Cycle Nitrogen Fixation • Capture and conversion of nitrogen into a useable form by plants

23. I. Nitrogen Cycle Cont. Nitrogen enters food web when plants absorb nitrogen compounds from soil. Consumers get nitrogen by eating plants or animals that contain nitrogen. Nitrogen is returned to the soil in several ways • Animals urinate • Organisms die • Organisms convert ammonia into nitrogen compounds 4. denitrification

24. II. The Phosphorous Cycle

25. II. Phosphorus Cycle Cont. Short-term Cycle • Phosphorus is cycled from the soil to producers and then from the producers to consumers. Long-term Cycle • Weathering or erosion of rocks that contain phosphorus slowly adds phosphorus to the cycle.

26. Terrestrial Biomes Section 3.2

27. I. Terrestrial Biomes • Biomes: • Classified by their plants, temperature, and precipitation • Climate: • Average weather conditions in an area • Includes temperature and precipitation

28. Tropical Rainforest

33. Coniferous Forest

34. Taiga… permafrost

35. Tundra

36. I. Ecological Succession A. The change in an ecosystem that happens when one community replaces another. i. Result of changing abiotic and biotic factors B. Two types of ecological successions i. Primary succession ii. Secondary succession http://www.youtube.com/watch?v=AWwe0udewD8

37. II. Primary Succession A. The establishment of a community in an area of exposed rock that does not have any topsoil

38. III. Secondary succession A. Orderly and predictable change that takes place after a community of organisms has been removed but soil remains intact

39. I. Population Dynamics Species might not be able to expand its population range • Cannot survive abiotic conditions found in expanded region

40. II. Population Limiting Factors There are two categories of limiting factors • Density-independent factors • Density-dependent factors.

41. IV. Density-Dependent Factors Any factor in the environment that depends on the number of members in a population per unit area • Biotic factors • Disease • Competition • Parasites

42. III. Density-Independent Factors Any factor in the environment that does not depend on the number of members in a population per unit area • Weather events • Fire • Human alterations of the landscape • Air, land, and water pollution

43. V. Population Growth Rate Population dynamics (changes) • Based on • Natality (birth rate) • Mortality (death rate) • Emigration (out) • Immigration (in)

44. I. Population Density Population Density • The number of organisms per unit area Spatial Distribution • Dispersion is the pattern of spacing of a population.

45. II. Population Growth Rate The population growth rate (PGR) • Explains how fast a given population grows Population dynamics (changes) • Based on… • Natality (birth rate) (+) • Mortality (death rate) (-) • Emigration (out) (-) • Immigration (in) (+)

46. III. Exponential Growth Rate Occurs when… growth rate is proportional to the size of the population B. All populations grow exponentially until… some limiting factor slows the population’s growth

47. IV. Logistic Growth Model A. The population’s growth slows or stops following exponential growth, at the population’s carrying capacity

48. V. Carrying Capacity Maximum number of individuals in a species that an environment can support for the long term Limited by energy, water, oxygen, and nutrients available

49. Preserving Biodiversity

50. I. What is biodiversity? The variety of life in an area • Determined by the number of different species in that area. Biodiversity increases • Stability of an ecosystem • Contributes to health of biosphere Types of Biodiversity • Species Diversity • Ecosystem Diversity