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Cellular respiration question

  1. Jul 8, 2007 #1
    i don't understand how the potential energy of a molecule of glucose and two molecules of pyruvic acid are different. Aren't they the same? 6-carbons(glucose) are broken down to 2 3-carbons molecules(pyruvic acid) what makes it different? please help >_< :confused:
  2. jcsd
  3. Jul 9, 2007 #2

    jim mcnamara

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    Staff: Mentor

    The energy is not stored in a count of carbon atoms. By this thinking six carbon dioxide molecules should have the same potential energy as a glucose molecule.

    The energy required to make atoms bond to other atoms to make molecules is where the energy is stored - bonds between atoms = potential energy. In glucose the carbon atoms are in a reduced state, when the bonds are broken (oxidized) the energy is released. The carbon is oxidized. The total stored energy goes down.

    When a molecule is split apart (1 glucose -> 2 pyruvate) some of the potential energy is lost. Because one of the bonds is broken by oxidation.

    This is kind of too simplified, but is the basic idea you seem to have have missed.
  4. Jul 11, 2007 #3
    ohh i get it now, so glucose would contain more potential energy since it is going through the process of glycolysis, energy is being released and the bonds being broken,
    okay thank you very much! :)
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