2 The study of the interactions between organisms and the living and nonliving components of their environment--- INTERDEPENDENCE (interconnectedness)!!
3 Ecological ModelsPhysical, conceptual, or mathematical representations of the components of an ecological systemUsed to help plan and evaluate solutions to environmental problems
4 Levels of Organization Ecologists have organized the interactions in which an organism takes part into different levels according to complexity.
5 1st Level of Organization Organism: An individual living thing that is made of cells, uses energy, reproduces, responds, grows, and develops
6 2nd Level of Organization Population: A group of organisms, all of the same species, which interbreed and live in the same place at the same time.
7 3rd Level of Organization BiologicalCommunity: All the populations of different species that live in the same place at the same time and interact (solely biotic in terms of composition).
8 4th Level of Organization Ecosystem: Populations of plants and animals that interact with each other in a given area, along with the abiotic components (physical and chemical) of that area. [terrestrial or aquatic]
9 5th Level of Organization Earth:apple::biosphere:skin of appleBiosphere: Broadest, most inclusive level, i.e., the thin volume of Earth and its atmosphere that supports life (5 to 6 miles above surface to deepest part of the oceans)
10 The Nonliving Environment Abiotic factors- the nonliving parts of an organism’s environment.Examples: temperature, humidity, pH, salinity, oxygen concentration, nitrogen availability, soil, and precipitation.
11 The Living Environment Biotic factors- all the living organisms that inhabit an environment.All organisms depend on others directly or indirectly for food, shelter, reproduction, or protection.
16 Organisms in a Changing Environment Acclimation: Adjusting tolerance to abiotic factors over the course of a lifetimeAdaptation: genetic change in a species or population that occurs from generation to generation over time
17 Control of Internal Conditions Conformers (Cold-Blooded): organisms that change their internal conditions as their external environment changesRegulators (Warm-Blooded): Organisms that use energy to control some of their internal conditionsDormancy: strategy for surviving unfavorable conditions through reduced activityMigration: strategy for surviving unfavorable conditions through moving to a more favorable habitat
18 Habitat & Niche Habitat is the place a plant or animal lives Niche is an organism’s total way of life, to include the range of conditions that it can tolerate, the resources it uses, the methods by which it obtains resources, the number of offspring it has, the time of reproduction, and all other interactions with the environmentGeneralist (e.g. opossum)Specialist (e.g. koala bear)
19 6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 (glucose) + 6O2 Energy TransferBegins with the SUNPhotosynthesis6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 (glucose) + 6O2
20 Energy TransferProducers: autotrophs that capture energy and use it to make organic molecules*Photosynthesis*ChemosynthesisBiomass: organic material that has been produced in an ecosystem
21 Energy TransferConsumers: heterotrophs that obtain energy by consuming organic molecules made by other organisms*Herbivores: eat producers*Carnivores: eat other consumers*Omnivores: eat both producersand consumers*Detritivores: feed on the “garbage” of an ecosystem-Decomposer: a detritivore that releases complex molecules that cause decay
22 Energy FlowTrophic Level: indicates organism’s position in a sequence of energy transfers*1st trophic level = producers*2nd trophic level = herbivores*3rd+trophic level = consumers-Higher trophic levels contain less energy,so they support fewer individuals
23 Food Chains and Food Webs Food Chain: single pathway of feeding relationships among organisms in an ecosystem that results in energy transferFood Web: Interrelated food chains in an ecosystemOn average, only 10% of the total energy consumed in one trophic level is incorporated into organisms in the next
24 Energy Pyramids Show :Amount of available energy decreases for higher consumersAmount of available energy decreases down the food chainIt takes a large number of producers to support a small number of primary consumersIt takes a large number of primary consumers to support a small number of secondary consumers
26 Ecosystem RecyclingAs energy and matter flow through an ecosystem, matter must be recycled and reused.Substances such as water, carbon, nitrogen, calcium, and phosphorus each pass between the living and nonliving worlds through biogeochemical cycles