Biochemical%20Cycles-%20closed%20circles%20or%20cycles%20of%20materials%20from%20nonliving%20to%20living%20organisms%20and%20back%20to%20nonliving.%20Examples%20:%20Water,%20carbon,%20nitrogen%20and%20phosphorus

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Biochemical Cycles- closed circles or cycles of
materials from nonliving to living organisms and
back to nonliving.Examples Water, carbon,
nitrogen and phosphorus

• Biology, Geology and Chemistry
• Cycles Nutrients through the Ecosystem

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I. General Information

• A. Biogeochemical cycles
• materials cycle between the living and physical
  (non-living) parts of an ecosystem
• B. Types of cycles
• 1. Water
• 2. Energy
• 3. Carbon
• 4. Nitrogen

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II. Water Cycle
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II. Water Cycle

• Driven by
• the Sun
• B. Steps of Water Cycle
• 1. Evaporation
• a. Sun heats Earth
• b. H2O evaporates
• c. H2O goes into atmosphere as
• H2O vapor

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II. Water Cycle

• 2. Condensation
• H2O condenses
• (goes from gas to liquid)
• to form
• clouds

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II. Water Cycle

• 3. Precipitation
• H2O leaves clouds, falls on Earth
• E.g. rain, snow, sleet, hail
• 4. Percolation / Infiltration
• H2O enters soil, becomes groundwater

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II. Water Cycle

• 5. Runoff
• Some H2O moves on surface to rivers,
  lakes oceans
• 6. Transpiration
• H2O released from plant leaves,
• returns to atmosphere

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II. Water Cycle

• C. Where is the H2O on Earth?
• 1. Oceans
• 97.2
• 2. Glaciers
• 2.15
• 3. Lakes
• 0.009
• 4. Soil
• 0.005
• 5. Atmosphere
• 0.001
• 6. Streams
• 0.0001

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II. Water Cycle
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III. Carbon Cycle
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III. Carbon Cycle

• How does carbon enter the
• living part of the cycle?
• 1. Photosynthesis
• Plants, algae, cyanobacteria use CO2 to
  make
• organic compounds (sugars)
• 2. Nutrients move C through trophic levels
• Consumers move organic compounds

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III. Carbon Cycle

• B. How does carbon get back into the physical
  part of the cycle?
• 1. Cellular Respiration
• O2 used
• to break down sugars
• CO2 released into
• atmosphere

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III. Carbon Cycle

• 2. Combustion
• Fossil fuels wood burned
• CO (carbon monoxide) released to atmosphere
• Factory Auto emissions release CO to
  atmosphere

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III. Carbon Cycle

• 4. Decomposition of waste and dead materials
• Some dead organisms become fossil fuels
• Some dead organisms and waste decay, returning
  nutrients to the soil
• Erosion
• CaCO2 from shells
• returned to system
• as sediment
• Shelled organisms die
• Sediment returns C to ecosystem by erosion (wind
  water)

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III. Carbon Cycle
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IV. Nitrogen Cycle
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IV. Nitrogen Cycle

• General information
• 1. N needed to make proteins
• Proteins large molecules that perform
  almost all of living organisms vital f(x)s
  (functions)

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IV. Nitrogen Cycle

• 2. N hard to convert into a form
• usable by plants
• 3. Most steps of N cycle occur in the soil
• 4. Bacteria very important to the N cycle

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IV. Nitrogen Cycle

• B. Steps of the N cycle
• 1. Nitrogen fixation
• Bacteria work with
• legumes
• (peas, beans, peanuts)
• to take N2 from atmosphere,
• put it into the soil

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IV. Nitrogen Cycle

• 2. Ammonification
• Animals plants deposit
• nitrogenous waste
• Decomposers
• (bacteria fungi) convert
• organic N
• (proteins) to ammonia (NH3)

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IV. Nitrogen Cycle

• 3. Nitrification
• Another kind of bacteria convert nitrogen
  compounds
• NH3 ? NH4 ? NO2- NO3-
• 4. Denitrification
• Another kind of bacteria
• convert nitrites and nitrates
• to nitrogen gas
• NO2- NO3- ? N2

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IV. Nitrogen Cycle

• 5. Assimilation- the absorption
• and incorporation of
• Nitrogen into plant and
• animal compounds

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IV. Nitrogen Cycle