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Steps of the Calvin Cycle:
(1) The enzyme RuBisCO catalyses the carboxylation of Ribulose-1,5-bisphosphate, a 5 carbon compound, by carbon dioxide (a total of 6 carbons) in a two-step reaction. The initial product of the reaction is a six-carbon intermediate so unstable that it immediately splits in half, forming two molecules of glycerate 3-phosphate, a 3-carbon compound. (also: 3-phosphoglycerate, 3-phosphoglyceric acid, 3PGA)
(2) The enzyme phosphoglycerate kinase catalyses the phosphorylation of 3PGA by ATP (which was produced in the light-dependent stage). 1,3-bisphosphoglycerate (glycerate-1,3-bisphosphate) and ADP are the products. (However, note that two PGAs are produced for every CO2 that enters the cycle, so this step utilizes 2ATP per CO2 fixed.
(3) The enzyme G3P dehydrogenase catalyses the reduction of 1,3BPGA by NADPH (which is another product of the light-dependent stage). Glyceraldehyde 3-phosphate (also G3P, GP, TP, PGAL) is produced, and the NADPH itself was oxidized and becomes NADP+. Again, two NADPH are utilized per CO2 fixed.
(Simplified versions of the Calvin cycle integrate the remaining steps, except for the last one, into one general step - the regeneration of RuBP - also, one G3P would exit here.)
(4) Triose phosphate isomerase converts some G3P reversibly into dihydroxyacetone phosphate (DHAP), also a 3-carbon molecule.
(5) Aldolase and fructose-1,6-bisphosphatase convert a G3P and a DHAP into fructose-6-phosphate (6C). A phosphate ion is lost into solution.
(6) Then fixation of another CO2 generates two more G3P.
(7) F6P has two carbons removed by transketolase, giving erythrose-4-phosphate. The two carbons on transketolase are added to a G3P, giving the ketose xylulose-5-phosphate (Xu5P).
(8) E4P and a DHAP (formed from one of the G3P from the second CO2 fixation) are converted into sedoheptulose-1,7-bisphosphate (7C) by aldolase enzyme.
(9) Sedoheptulose-1,7-bisphosphatase (one of only three enzymes of the Calvin cycle which are unique to plants) cleaves sedoheptulose-1,7-bisphosphate into sedoheptulose-7-phosphate, releasing an inorganic phosphate ion into solution.
(10) Fixation of a third CO2 generates two more G3P. The ketose S7P has two carbons removed by transketolase, giving ribose-5-phosphate (R5P), and the two carbons remaining on transketolase are transferred to one of the G3P, giving another Xu5P. This leaves one G3P as the product of fixation of 3 CO2, with generation of three pentoses which can be converted to Ru5P.
(11) R5P is converted into ribulose-5-phosphate (Ru5P, RuP) by phosphopentose isomerase. Xu5P is converted into RuP by phosphopentose epimerase.
(12) Finally, phosphoribulokinase (another plant unique enzyme of the pathway) phosphorylates RuP into RuBP, ribulose-1,5-bisphosphate, completing the Calvin cycle. This requires the input of one ATP.
SHORTER ANSWER : The Calvin cycle uses ATP and NADPH from the light-depenedent reactions to produce high-energy sugars.
What else can I help you with?
What reaction process makes sugar?
The Calvin cycle.
Where does the Calvin cycle occurred in?
The Calvin cycle occurs in the stroma of chloroplasts. Chloroplasts are plants that contain the pigment chlorophyll, which makes plants green.
Photosynthesis and cellular respiration make up this cycle?
Calvin cycle
What is another name for the for the dark reaction?
the calvin cycle
Which organelle participates in the Calvin cycle?
The chloroplast is the organelle that participates in the Calvin cycle. Within the chloroplast, the stroma is where the Calvin cycle takes place.
What are other names for the Calvin cycle?
The Calvin Cycle is also known as the Calvin-Benson Cycle, light-independent reaction, or the C3 Cycle.
What makes the Calvin cycle a cycle?
The Calvin cycle is a cycle because it begins and ends with the same molecule, ribulose-1,5-bisphosphate (RuBP). This molecule is regenerated at the end of the cycle after it undergoes a series of reactions that produce sugars used by the plant for energy.
What site does Calvin cycle happen?
The Calvin cycle occurs in the stroma of chloroplasts.
When does carbohydrate production occur in a chloroplast?
During The Calvin Cycle cycle, sugars are produced in the chloroplast.
The Calvin Cycle is known as what?
The Calvin Cycle is also known as the dark phase of photosynthesis.
Where in the plant does the Calvin cycle occur?
The Calvin Cycle occurs in the stroma (inside a chloroplast)
Name the metabolic pathway of photosynthesis in which carbon dioxide is converted into glucose using ATP?
The Calvin cycle, also known as the light-independent reactions, is the metabolic pathway of photosynthesis in which carbon dioxide is converted into glucose using ATP. This process occurs in the stroma of the chloroplasts.
