Nitrogen Cycle

1
Nitrogen Cycle

• Ch.2.2

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Bacteria Decomposers in the Nitrogen Cycle
3
Bacteria as decomposers
4
Legumes Root nodules

• Legumes are plants with root nodules
• Fix nitrogen in soil
• Using Bacteria
• Produce usable Nitrate

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Legumes have root nodules
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Nitrogen Diagram

• A-C Nitrogen gas is fixed by lightning to nitrate
  in the soil (Nitrogen fixation)
• B-G Ammonia from waste decomposes to nitrite by
  bacteria (nitrification)
• G-C Nitrite is converted to nitrate by bacteria
  (nitrification)

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• D-A Soil nitrate becomes nitrogen gas
  (denitrification)
• C-E Nitrate is used as fertilizer by plants
• E-F plant protein nitrogen becomes animal protein
  when eaten
• F-B Animal protein waste decomposes to ammonia by
  bacteria

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IV. Nitrogen cycle

• Plants only use nitrate
• Muscle tissue is made of amino acids
• Decomposition of protein makes ammonia
• Ammonia converts to nitrite
• Nitrite converts to nitrate

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V. Nitrogen Cycle

• Nitrification ammonia to nitrite
• nitrite to nitrate by bacteria in the soil
• Denitrification nitrate to nitrogen gas by
  bacteria
• Decompostion ammonia in wastes to nitrite by
  bacteria
• Nitrogen fixation nitrogen gas to nitrateby
  lightning or nitrite by plant/ bacteria