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The Calvin Cycle fixes CO<sub>2</sub> to produce carbohydrates. It is a set of redox reactions.&nbsp;<ref>Hardin J. et al, Becker's world of the cell 8th edition, Boston, Benjamin Cummings: page 309</ref>&nbsp;Three [[Ribulose bisphospate|ribulose bisphospate]] molecules fix three CO<sub>2</sub> molecules, producing six molecules of of 3-[[Phosphoglycerate|phosphoglycerate]]; this is then reduced to [[1,3-bisphosphoglycerate|1,3-bisphosphoglycerate]] using a [[Phosphate group|phosphate group]] from [[ATP|ATP]], producing [[ADP|ADP]] as a by-product. This, in turn, is reduced to [[Glyceraldehyde-3-phosphate|glyceraldehyde-3-phosphate]] by the [[Oxidation|oxidation]] of [[NADPH|NADPH]] to [[NADP+|NADP+]] and an inorganic phosphate.<ref>Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science : page 845</ref> One out of every six GP molecules goes on to synthesise a [[Carbohydrate|carbohydrate]], whilst the other five regenerate ribulose bisphospate to allow the cycle to continue.<ref>Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings: page 311</ref> The five GP molecules are converted to five molecules of glyceraldehyde-3-phospate, which then form 3 molecules of ribulose-5-phosphate. The ribulose-5-phosphate is then reduced via the reduction of ATP to ADP to reform the original 3 molecules of ribulose bisphospate.<ref>Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science: page 845</ref> The Calvin Cycle occurs in the stomata of photosynthesising organisms, and was named after [[Melvin Calvin|Melvin Calvin]], who received a Nobel Prize in 1961 for his work on the subject.<ref>Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings:page 309</ref>&nbsp;<br>
The Calvin Cycle fixes CO<sub>2</sub> to produce [[Carbohydrate|carbohydrates]]. It is a set of [[Redox_reaction|redox ]]reactions.&nbsp;<ref>Hardin J. et al, Becker's world of the cell 8th edition, Boston, Benjamin Cummings: page 309</ref>&nbsp;Three [[Ribulose bisphospate|ribulose bisphospate]] molecules fix three CO<sub>2</sub> molecules, producing six molecules of of 3-[[Phosphoglycerate|phosphoglycerate]]; this is then reduced to [[1,3-bisphosphoglycerate|1,3-bisphosphoglycerate]] using a [[Phosphate group|phosphate group]] from [[ATP|ATP]], producing [[ADP|ADP]] as a by-product. This, in turn, is reduced to [[Glyceraldehyde-3-phosphate|glyceraldehyde-3-phosphate]] by the [[Oxidation|oxidation]] of [[NADPH|NADPH]] to [[NADP+|NADP+]] and an inorganic phosphate.<ref>Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science : page 845</ref> One out of every six GP molecules goes on to synthesise a [[Carbohydrate|carbohydrate]], whilst the other five regenerate ribulose bisphospate to allow the cycle to continue.<ref>Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings: page 311</ref> The five GP molecules are converted to five molecules of glyceraldehyde-3-phospate, which then form 3 molecules of ribulose-5-phosphate. The ribulose-5-phosphate is then reduced via the reduction of [[ATP|ATP ]]to [[ADP|ADP ]]to reform the original 3 molecules of ribulose bisphospate.<ref>Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science: page 845</ref> The Calvin Cycle occurs in the stomata of [[Photosynthesis|photosynthesising ]]organisms, and was named after [[Melvin Calvin|Melvin Calvin]], who received a Nobel Prize in 1961 for his work on the subject.<ref>Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings:page 309</ref>&nbsp;<br>


=== References  ===
=== References  ===


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Latest revision as of 14:52, 18 October 2016

The Calvin Cycle fixes CO2 to produce carbohydrates. It is a set of redox reactions[1] Three ribulose bisphospate molecules fix three CO2 molecules, producing six molecules of of 3-phosphoglycerate; this is then reduced to 1,3-bisphosphoglycerate using a phosphate group from ATP, producing ADP as a by-product. This, in turn, is reduced to glyceraldehyde-3-phosphate by the oxidation of NADPH to NADP+ and an inorganic phosphate.[2] One out of every six GP molecules goes on to synthesise a carbohydrate, whilst the other five regenerate ribulose bisphospate to allow the cycle to continue.[3] The five GP molecules are converted to five molecules of glyceraldehyde-3-phospate, which then form 3 molecules of ribulose-5-phosphate. The ribulose-5-phosphate is then reduced via the reduction of ATP to ADP to reform the original 3 molecules of ribulose bisphospate.[4] The Calvin Cycle occurs in the stomata of photosynthesising organisms, and was named after Melvin Calvin, who received a Nobel Prize in 1961 for his work on the subject.[5] 

References

  1. Hardin J. et al, Becker's world of the cell 8th edition, Boston, Benjamin Cummings: page 309
  2. Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science : page 845
  3. Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings: page 311
  4. Alberts B. et al, Molecular Biology of the Cell 5th edition, 2008, New York, Garland Science: page 845
  5. Hardin J. et al, Becker's World of the Cell 8th edition, 2012, Boston, Benjamin Cummings:page 309