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The Carbon Cycle

Answer the following questions.
(Use lower case only.)

  1) Pick the correct gas from the list below to answer questions a - h.  
    Oxygen        Nitrogen        Argon        Carbon Dioxide
  a) Which gas in the air is needed for wood to burn?  
  b) When wood burns, water vapour is made - and what else?  
  c) Complete the word equation for burning using b) and a).  
    wood +      water +    
  d) Which gas in the air do we need to breathe in to stay alive?  
  e) Which gas produced by respiration do we breathe out?  
  f) Complete the word equation for respiration using d) and e).  
    glucose +      water +    
  g) Which gas is needed, along with water, for photosynthesis?  
  h) Which gas is produced, along with glucose, by photosynthesis?  
  2) Fill in the gaps in the following paragraph on the Carbon Cycle with the correct words?  
    Plants make glucose from     and water. This process is called .    It     the amount of carbon dioxide in the air, and produces .    Animals, plants and bacteria produce energy from oxygen by the process of .    This process releases     into the air. When wood and other fuels are ,    oxygen from the air is used up, and water vapour and      are produced. Carbon dioxide is also produced by     and fungi, when they break down materials in     animals and plants, or in animal and plant waste. This process is called decay or .     
  3) Which of the following respire? Answer yes or no  
    A bacterium    
    A daffodil    
    A table    
    A piece of coal    
    A river    
You scored