C-3 cycle
Quick Summary
The C-3 cycle, also known as the Calvin-Benson cycle, is a fundamental process in photosynthesis where plants convert carbon dioxide into sugars. This cycle occurs in the stroma of chloroplasts and uses the chemical energy from ATP and NADPH, produced during the light-dependent reactions. The key step is carbon fixation, where the enzyme RuBisCO attaches carbon dioxide to a five-carbon compound (RuBP). This forms an unstable six-carbon molecule that splits into three-carbon compounds. These compounds are then converted into high-energy sugar molecules, like glucose, which the plant uses for energy and growth. Some of the sugar is recycled to regenerate RuBP, allowing the cycle to continue.1234
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photosynthesisThe Calvin-Benson cycleIn many plant species, often referred to as C3 plants, carbon fixation and reduction occurs in the stroma of the chloroplast in a three-carbon pathway known as the Calvin-Benson cycle. This cycle, involves the formation of intermediate sugar phosphates in a cyclic sequence.…
Read MoreIn many plant species, often referred to as C3 plants, carbon fixation and reduction occurs in the stroma of the chloroplast in a three-carbon pathway known as the Calvin-Benson cycle. This cycle, involves the formation of intermediate sugar phosphates in a cyclic sequence.…
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plantBasic mechanisms…series of reactions called the Calvin-Benson cycle. This reaction yields an unstable six-carbon intermediate, which immediately breaks down into two molecules of phosphoglycerate (PGA), a three-carbon acid. Each reaction is catalyzed by a specific enzyme. Six revolutions of the cycle means that 6 CO2 molecules react with 6 RuBP molecules…
Read More…series of reactions called the Calvin-Benson cycle. This reaction yields an unstable six-carbon intermediate, which immediately breaks down into two molecules of phosphoglycerate (PGA), a three-carbon acid. Each reaction is catalyzed by a specific enzyme. Six revolutions of the cycle means that 6 CO2 molecules react with 6 RuBP molecules…
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algaePhotosynthesis and light-absorbing pigments…reactions and dark reactions (or Calvin cycle). During the dark reactions, carbon dioxide is bound to ribulose bisphosphate, a 5-carbon sugar with two attached phosphate groups, by the enzyme ribulose bisphosphate carboxylase. This is the initial step of a complex process leading to the formation of sugars. During the light…
Read More…reactions and dark reactions (or Calvin cycle). During the dark reactions, carbon dioxide is bound to ribulose bisphosphate, a 5-carbon sugar with two attached phosphate groups, by the enzyme ribulose bisphosphate carboxylase. This is the initial step of a complex process leading to the formation of sugars. During the light…
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PoaceaeCharacteristic morphological features…which synthesizes a three-carbon (C-3) compound. The chief distinction between these two pathways is the presence of specialized, thick-walled photosynthetic cells located in sheaths surrounding vascular bundles in C-4 plants. These cells participate in the mechanism for assimilation of carbon dioxide from the atmosphere into a four-carbon compound. Hence,…
Read More…which synthesizes a three-carbon (C-3) compound. The chief distinction between these two pathways is the presence of specialized, thick-walled photosynthetic cells located in sheaths surrounding vascular bundles in C-4 plants. These cells participate in the mechanism for assimilation of carbon dioxide from the atmosphere into a four-carbon compound. Hence,…
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