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Home > Biology > The biosphere > How the biosphere works


How the biosphere works


For your biology exam you should be able to:

  • identify food chains from a food web
  • explain how removing one organism from a food web will affect the number of other organisms in that food web
  • explain what is meant by 'pyramids of number' and 'pyramids of biomass'
  • give examples of factors that limit population growth
  • state what competition is
  • describe the sequences of the nitrogen cycle

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