The Nitrogen cycle

• What is nitrogen needed for?

  Proteins, amino acids, DNA and ATP
• The nitrogen cycle

  A) Dead organic matter

  B) saprobionts

  C) Ammonification

  D) Ammonium ions

  E) Nitrite ions

  F) nitrate ions

  G) Nitrification

  H) Nitrifying bacteria

  I) Denitrification

  J) Denitrifying bacteria

  K) Nitrogen fixation

  L) legumes

  M) free living nitrogen fixing bacteria

  N) symbiotic nitrogen fixing bacteria

  
• What is ammonification?


  The breakdown of proteins to ammonium ions when an organism dies
• What is nitrification?


  The process of bacteria chemically altering ammonium ions to nitrite ions
• Why is nitrite converted into nitrate?


  Nitrate is more soluble, so can be easily absorbed
• What is denitrification?


  Converting nitrate to nitrogen
• Which bacteria is involved in denitrification?

  denitrifying bacteria
• Where does denitrification happen?

  In anaerobic conditions (water logged soil)
• Which bacteria converts dead organic matter into ammonium ions?

  Saprobionts
• What bacteria is involved in nitrification?

  Nitrifying bacteria
• What is the process of converting ammonium ions to nitrate ions?

  Nitrification
• What are the 2 natural methods of nitrogen fixing?

  • Rain or lightening
  • Nitrogen fixing bacteria
• How does free living bacteria carry out nitrogen fixation?

  converts atmospheric nitrogen into ammonium ions and then nitrate ions
• Where do symbiotic nitrogen fixing bacteria live?

  The root nodules of legumes
• What conditions do free living bacteria work in?

  Aerobic
• What conditions do symbiotic nitrogen fixing bacteria work in?

  Anaerobic
• How is symbiotic bacteria mutualistic?

  The legume gives the bacteria glucose for respiration

  The bacteria gets the plant nitrogen for growth
• What do inorganic fertilisers have a specific ratio of?

  nitrates, phosphates and potassium
• What are some problems with artificial fertilisers?

  Rain carries fertiliser into the lakes and rivers (leaching) and contaminates them (eutrophication)
• What are some examples of organic fertilisers?

  bone meal, compost, manure, fish meal, slurry