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Ecological Cycles
Energy is used up, but materials are recycled
Cycling of materials between the environment and organisms.
Chemical and biological processes
Examples Carbon cycle Water cycle Nitrogen cycle
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Carbon Cycle
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Carbon Cycle
Carbon found in atmosphere, soil, oceans, fossil deposits, living organisms
Flows from photosynthetic organisms through food chains
Returned to atmosphere by combustion and respiration
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Water Cycle
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Water Cycle
Continuous circulation of moisture Between atmosphere – surface of Earth Water cycles from gas to liquid states
Precipitation Transpiration Evaporation
Cycle is driven by energy from the sun
Animation
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Nitrogen Cycle
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• Essential for all living organisms to create protein• Usable for organisms if “fixed”• Often combined with Oxygen, Hydrogen, or Carbon
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Cycle Labels
Carbon Cycle Respiration Animals Photosynthesis Bicarbonate Plants Decomposition Diffusion Dissolved CO2 CO2 in Atmosphere Carbonate in Sediment
Water Cycle Runoff Solar Energy Precipitation Ocean Runoff and
Groundwater Evapotranspiration
Nitrogen Cycle Assimilation Nitrogen-fixing in root
nodules Decomposition: fungi &
bacteria
