The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle[1] of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose. The Calvin cycle is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. In plants, these reactions occur in the stroma, the fluid-filled region of a chloroplast outside the thylakoid membranes. These reactions take the products (ATP and NADPH) of light-dependent reactions and perform further chemical processes on them. The Calvin cycle uses the chemical energy of ATP and reducing power of NADPH from the light dependent reactions to produce sugars for the plant to use. These substrates are used in a series of reduction-oxidation (redox) reactions to produce sugars in a step-wise process; there is no direct reaction that converts several molecules of CO2 to a sugar. There are three phases to the light-independent reactions, collectively called the Calvin cycle: carboxylation, reduction reactions, and ribulose 1,5-bisphosphate (RuBP) regeneration.
Though it is also called the "dark reaction," the Calvin cycle does not actually occur in the dark or during night time. This is because the process requires NADPH, which is short-lived and comes from light-dependent reactions. In the dark, plants instead release sucrose into the phloem from their starch reserves to provide energy for the plant. The Calvin cycle thus happens when light is available independent of the kind of photosynthesis (C3 carbon fixation, C4 carbon fixation, and crassulacean acid metabolism (CAM)); CAM plants store malic acid in their vacuoles every night and release it by day to make this process work.[2]
^Silverstein, Alvin (2008). Photosynthesis. Twenty-First Century Books. p. 21. ISBN 9780822567981.
^Cushman, John C. (2001). "A plastic photosynthetic adaptation to arid environments". Plant Physiology. 127 (4): 1439–1448. doi:10.1104/pp.010818. PMC 1540176. PMID 11743087.
The Calvincycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle of photosynthesis is...
Melvin Ellis Calvin (April 8, 1911 – January 8, 1997) was an American biochemist known for discovering the Calvincycle along with Andrew Benson and James...
cycle is known as the Calvincycle, but many scientists refer to it as the Calvin-Benson, Benson-Calvin, or even Calvin-Benson-Bassham (or CBB) Cycle...
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The citric acid cycle—also known as the Krebs cycle, Szent–Györgyi–Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of biochemical...
back to the bundle sheath where it enters the conversion phase of the Calvincycle. For each CO2 molecule exported to the bundle sheath the malate shuttle...
Melvin Calvin, Andrew Benson and James Bassham in 1950. C3 carbon fixation occurs in all plants as the first step of the Calvin–Benson cycle. (In C4...
make organic molecules from carbon dioxide in a process known as the Calvincycle. Chloroplasts carry out a number of other functions, including fatty...
(triphosphopyridine nucleotide), is a cofactor used in anabolic reactions, such as the Calvincycle and lipid and nucleic acid syntheses, which require NADPH as a reducing...
processes are used in their primary metabolism like the photosynthetic Calvincycle and crassulacean acid metabolism. Others make specialised materials like...
position through thermal fluctuation. RuBisCO is one of many enzymes in the Calvincycle. When Rubisco facilitates the attack of CO2 at the C2 carbon of RuBP...
addition of carbon dioxide to RuBP (carboxylation), a key step in the Calvin–Benson cycle, but approximately 25% of reactions by RuBisCO instead add oxygen...
HOCH2C(O)CH2OPO32-. This anion is involved in many metabolic pathways, including the Calvincycle in plants and glycolysis. It is the phosphate ester of dihydroxyacetone...
The carbon cycle is that part of the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere...
reversible conversion is required for carbon fixation in plants – through the Calvincycle – and for the nonoxidative phase of the pentose phosphate pathway. This...
Hurricane Calvin (disambiguation), various Pacific Ocean cyclones CalvinCycle, a biochemical system involved in production of sugars Calvin (horse), an...
generated from ADP and inorganic phosphate. ATP is essential in the Calvincycle to assist in the synthesis of carbohydrates from carbon dioxide and NADPH...
participates in both the pentose phosphate pathway in all organisms and the Calvincycle of photosynthesis. Transketolase catalyzes two important reactions, which...
+ 2 H+ + 3 ATP + O2 The light-independent reactions undergo the Calvin-Benson cycle, in which the energy from NADPH and ATP is used to convert carbon...
degraded in the mitochondrial citric acid cycle, thereby providing additional CO2 molecules for the CalvinCycle. Pyruvate can also be used to recover PEP...
C3 plant uses the Calvincycle for the initial steps that incorporate CO2 into organic material. A C4 plant prefaces the Calvincycle with reactions that...
in English-speaking populations. Melvin Calvin (1911–1997), American chemist who discovered the Calvincycle Melvin Day (1923–2016), New Zealand artist...
reduction cycle, a.k.a. the Calvincycle. All amino acids are formed from intermediates in the catabolic processes of glycolysis, the citric acid cycle, or...
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