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Cycles of Matter. Cycling of Matter. Cycles in the Biosphere. Energy is transformed into usable forms to support the functions of an ecosystem. The cycling of nutrients in the biosphere involves both matter in living organisms and physical.
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Cycling of Matter Cycles in the Biosphere • Energy is transformed into usable forms to support the functions of an ecosystem. • The cycling of nutrients in the biosphere involves both matter in living organisms and physical processes found in the environment such as weathering.
Cycling of Matter • Elements, chemical compounds, and other forms of matter are passed from one organism to another and from one part of the biosphere to another through biogeochemical cycles. • Matter can cycle because biological systems do not use up matter, they transform it. • Matter is assembled into living tissue or passed out of the body as waste products.
2.3 Cycling of Matter The Water Cycle
H20 Cycle • Why is water important • Cells are 70% - 90% H2O • H2O is medium for metabolic functions • Terrestrial organisms must prevent desiccation (drying out)
Cycling of Matter • Approximately 90 percent of water vapor evaporates from oceans, lakes, and rivers; 10 percent evaporates from the surface of plants through a process called transpiration. • Freshwater constitutes only about 3 percent of all water on Earth. • About 69 percent of all freshwater is found in ice caps and glaciers.
Steps of the Water (H2O) Cycle Evaporation Transpiration Condensation (Clouds) Precipitation (Rain) Surface runoff
Cycling of Matter The Carbon and Oxygen Cycles
Cycling of Matter • Carbon and oxygen often make up molecules essential for life. • Carbon and oxygen recycle relatively quickly through living organisms.
Carbon Cycle • Components • Photosynthesis – • 6H2O + 6CO2 C6H12O6 + 6O2 • Respiration • C6H12O6 + 6O2 6H2O + 6CO2 • Decomposition
Steps of Carbon Cycle Plant leaves take CO2 from the air Plants Store C & Energy in C6H12O6 Plants & Animals release CO2 into the air Decomposers return C back to environment
Cycling of Matter Long-term Cycle • Organic matter converted to peat, coal, oil, or gas deposits (carbon) • Calcium carbonate (carbon and oxygen) Short-term Cycle • Burning fossil fuels (carbon)
Cycling of Matter The Nitrogen Cycle • The capture and conversion of nitrogen into a form that is useable by plants is called nitrogen fixation.
Nitrogen Cycle • Needed by all organisms • Used to make proteins & nucleic acids • Air is 80% nitrogen • Cyantobacteria & Rhizobiumbacteria can use nitrogen directly from the air through nitrogen fixation
Steps in Nitrogen Cycle Cyanobacteria & Rhizobiumtake N2 from air (nitrogen fixation) Convert N2 to Ammonia Bacteria change ammonia to nitrates Plants use nitrates to make proteins Consumers eat plants Decomposers break down dead things into ammonia (ammonification) Anaerobic bacteria release N2 in to the air (denitrification)
Cycling of Matter • Nitrogen enters the food web when plants absorb nitrogen compounds from soil. • Consumers get nitrogen by eating plants or animals that contain nitrogen.
Cycling of Matter • Nitrogen is returned to the soil in several ways: • Animals urinate. • Organisms die. • Organisms convert ammonia into nitrogen compounds.
Cycling of Matter The Phosphorus Cycle
Cycling of Matter 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.
Chapter Diagnostic Questions What is a chemical substance that an organism must obtain from its environment to survive? biomass energy matter nutrient
Formative Questions Which biogeochemical cycle involves evaporation, transpiration, precipitation and runoff? carbon cycle nitrogen cycle phosphorus cycle water cycle
Formative Questions Which process in this cycle converts carbon dioxide and water into carbohydrates?
combustion of deposition of fossil fuels dead material Formative Questions photosynthesis respiration
Standardized Test Practice Which process returns nitrogen to the food web? decomposition denitrification nitrification nitrogen fixation