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The study of the interactions between organisms and the living and nonliving components of their environment---INTERDEPENDENCE (interconnectedness)!!
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Ecological Models
Physical, conceptual, or mathematical representations of the components of an ecological system
Used to help plan and evaluate solutions to environmental problems
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Levels of OrganizationLevels of Organization
EcologistsEcologists have organized the have organized the interactions in which an organism interactions in which an organism takes part into different levels takes part into different levels according to complexity.according to complexity.
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11stst Level of Organization Level of Organization
Organism:Organism:An individual An individual living thing that living thing that is made of is made of cells, cells, uses energy, uses energy, reproduces, reproduces, responds, responds, grows, and grows, and developsdevelops
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22ndnd Level of Organization Level of Organization
• Population:Population:A group of A group of organisms, all organisms, all of the of the same same speciesspecies, which , which interbreedinterbreed and and live in the live in the same place at same place at the same the same timetime..
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33rdrd Level of Organization Level of Organization
BiologicalBiological
Community:Community:All the All the populations populations of different speciesof different species that live in the that live in the same place at the same place at the same time and same time and interact (solely interact (solely biotic in terms of biotic in terms of composition).composition).
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44thth Level of Organization Level of Organization
Ecosystem:Ecosystem: Populations of plants Populations of plants and animals that and animals that interact with each interact with each other in a given other in a given area, along with the area, along with the abiotic components abiotic components (physical and (physical and chemical) of that chemical) of that area. area. [[terrestrial or terrestrial or aquatic]aquatic]
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55thth Level of Organization Level of Organization
Biosphere:Biosphere:Broadest, most Broadest, most inclusive level, inclusive level, i.e., the thin i.e., the thin volume of Earth volume of Earth and its and its atmosphere that atmosphere that supports life (5 to supports life (5 to 6 miles above 6 miles above surface to deepest surface to deepest part of the oceans)part of the oceans)
•Earth:apple::biosphere:skin of Earth:apple::biosphere:skin of appleapple
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The Nonliving The Nonliving EnvironmentEnvironment
Abiotic factorsAbiotic factors- the - the nonliving parts of an nonliving parts of an organism’s environment.organism’s environment.
Examples:Examples: temperature, temperature, humidity, pH, salinity, humidity, pH, salinity, oxygen concentration, oxygen concentration, nitrogen availability, soil, nitrogen availability, soil, and precipitation.and precipitation.
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The Living EnvironmentThe Living Environment
Biotic factorsBiotic factors- all the - all the living organisms that living organisms that inhabit an environment.inhabit an environment.
All All organisms depend organisms depend on others directly or on others directly or indirectlyindirectly for food, for food, shelter, reproduction, or shelter, reproduction, or protection.protection.
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Organisms in a Changing Environment
Acclimation: Adjusting tolerance to abiotic factors over the course of a lifetime
Adaptation: genetic change in a species or population that occurs from generation to generation over time
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Control of Internal ConditionsConformers (Cold-Blooded): organisms that change their internal conditions as their external environment changes
Regulators (Warm-Blooded): Organisms that use energy to control some of their internal conditions
Dormancy: strategy for surviving unfavorable conditions through reduced activity
Migration: strategy for surviving unfavorable conditions through moving to a more favorable habitat
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Habitat & NicheHabitat & Niche
HabitatHabitat 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 environment– Generalist (e.g. opossum) Generalist (e.g. opossum) – Specialist (e.g. koala bear)Specialist (e.g. koala bear)
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•Begins with the Begins with the SUNSUN
•PhotosynthesisPhotosynthesis
6CO2 + 6H2O + sunlight & chlorophyll C6H12O6 (glucose) + 6O2
Energy Transfer
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Energy Transfer
Producers: autotrophs that capture energy and use it to make organic molecules *Photosynthesis *Chemosynthesis
Biomass: organic material that has been produced in an ecosystem
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Energy TransferConsumers: heterotrophs that obtain energy by consuming organic molecules made by other organisms *Herbivores: eat producers *Carnivores: eat other consumers *Omnivores: eat both producers and consumers *Detritivores: feed on the “garbage” of an ecosystem -Decomposer: a detritivore that releases complex molecules that cause decay
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Energy Flow
Trophic 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
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Food Chains and Food Webs
Food Chain: single pathway of feeding relationships among organisms in an ecosystem that results in energy transfer
Food Web: Interrelated food chains in an ecosystem
On average, only 10% of the total energy consumed in one trophic
level is incorporated into organisms in the next
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Energy Pyramids Show :Amount of available Amount of available energy energy decreasesdecreases for for higher consumershigher consumersAmount of available Amount of available energy energy decreasesdecreases down down the food chainthe food chainIt takes a It takes a large number large number of producersof producers to support a to support a small number of primary small number of primary consumersconsumersIt takes a It takes a large number large number of primary consumersof primary consumers to to support a small number of support a small number of secondary consumerssecondary consumers
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Ecosystem Recycling
As 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