Khan Academy photosynthesisA kind of energy that is derived from present day photosynthesisCAM plantCalvin cycle 3 stagesC3 pathwayC4 PlantCalvin cycle enzymeKevin cycle biologyThe Calvin Cycle - Hyperphysics
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Carbon dioxide is captured in a cycle of reactions known as the Calvin cycle or the Calvin-Benson cycle after its discoverers. It is also known as just the ... TheCalvinCycle Clickonanypartofthediagramformoredetail. Plantsuseenergyfromthesunintinyenergyfactoriescalledchloroplasts.Usingchlorophyllintheprocessofphotosynthesis,theyconvertthesun'senergyintostorableforminorderedsugarmoleculessuchasglucose.Inthisway,carbondioxidefromtheairandwaterfromthesoilinamoredisorderedstatearecombinedtoformthemoreorderedsugarmolecules. CarbondioxideiscapturedinacycleofreactionsknownastheCalvincycleortheCalvin-Bensoncycleafteritsdiscoverers.ItisalsoknownasjusttheC3cycle.ThoseplantsthatutilizejusttheCalvincycleforcarbonfixationareknownasC3plants.Carbondioxidediffusesintothestromaofchloroplastsandcombineswithafive-carbonsugar,ribulose1,5-biphosphate(RuBP).TheenzymethatcatalyzesthisreactionisreferredtoasRuBisCo,alargemoleculethatmaybethemostabundantorganicmoleculeontheEarth.Thiscatalyzedreactionproducesa6-carbonintermediatewhichdecaysalmostimmediatelytoformtwomoleculesofthe3-carboncompound3-phosphoglycericacid(3PGA).Thefactthatthis3-carbonmoleculeisthefirststableproductofphotosynthesisleadstothepracticeofcallingthiscycletheC3cycle. InC3plantsthephotosynthesis,carbonfixationandCalvincyclealloccurinasinglechloroplast. InC4plantsthephotosynthesistakesplaceinachloroplastofathin-walledmesophyllcellanda4-carbonacidishandedofftoathick-walledbundlesheathcellwheretheCalvincycleoccursinachloroplastofthatsecondcell.ThisprotectstheCalvincyclefromtheeffectsofphotorespiration. InCAMplantsthephotosynthesisandinitialcarbonfixationoccuratnightanda4-carbonacidisstoredinthecell'svacuole.Duringtheday,theCalvincycleoperatesinthesamechloroplasts. EnergyfromATPandfromthereducedcoenyzmeNADPHisusedtoremoveaphosphategroupfrom3PGAandreducetheresultingdiphosphoglycerate(DPGA)toproducethe3-carbonsugarglyceraladehyde-3-phosphate(G3P).SomeofthisG3PisusedtoregeneratetheRuBPtocontinuethecycle,butsomeisavailableformolecularsynthesisandisusedtomakefructosediphosphate.Thefructosediphosphateisthenusedtomakeglucose,sucrose,starchandothercarbohydrates. Energycycleinlivingthings IndexPhotosynthesisConceptsReferenceMoore,etal.Ch7 HyperPhysics*****BiologyRNave GoBack
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- 1Sweet Secret | National Geographic Society
The Calvin cycle is a process that plants and algae use to turn carbon dioxide from the air into ...
- 25.3: The Calvin Cycle – Concepts of Biology
The Calvin cycle reactions (Figure 5.15) can be organized into three basic stages: fixation, redu...
- 3Calvin cycle - Wikipedia
The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynth...
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The Calvin cycle is the second stage in photosynthesis, where solar energy is used to fix carbon ...
- 5Calvin Cycle - an overview | ScienceDirect Topics
The Calvin cycle, which is also called the reductive pentose phosphate cycle, is the most widespr...
