In the regeneration phase, traffic which is RuBP regenerated required to react with additional traf

Dark reaction is the formation of sugars from CO2 reaction that occurs in the stroma. This reaction does not require light. The reaction occurs in the chloroplast is called the stroma. Dark reactions in plants can occur via two pathways, namely the Calvin-Benson cycle and Hatch-Slack traffic cycle. In general, the dark reactions can be divided into three stages (phases), ie fixation, reduction, and regeneration.
In the Calvin-Benson cycle plants change ribulose 1,5 bisphosphate compound into a compound with three carbon atoms, namely the amount of the compound 3-phosphogliserat. Hence plants that run through this dark reaction traffic called C-3 plants. Tethering CO2 as a carbon source in the plant aided by enzymes RuBisCo. Plants were dark reactions following the Hatch-Slack pathway called C-4 plants due to compounds formed after CO2 sequestration is oxaloacetate which has four carbon atoms. Enzyme that plays a role is phosphoenolpyruvate carboxilase. a. Calvin-Benson traffic cycle
The mechanism of the Calvin-Benson cycle begins with CO2 fixation by ribulose diphosphate carboxylase (RuBP) to form 3-phosphoglycerate. traffic RuBP is alosetrik enzyme stimulated by three types of changes resulting from the illumination of chloroplasts. traffic First, the reaction of this enzyme is stimulated by an increase in pH. If chloroplasts are given light, traffic H + ions are transported from the stroma into the thylakoid stroma resulted in increased pH stimulates the enzyme carboxylase, located on the outer surface of the thylakoid membrane. Second, this reaction is stimulated by Mg 2 +, which enters the stroma leaves as H + ions, if chloroplasts were given light. Third, this reaction is stimulated by NADPH, which is produced by photosystem I light during administration.
CO2 fixation is a dark reaction stimulated by illumination of chloroplasts. Ksasi Fi O2 through the process of carboxylation, reduction, and regeneration. Carboxylation involves the addition of CO2 and H2O to RuBP to form two molecules of 3-phosphoglycerate (3-PGA). Then the reduction phase, the carboxyl group in 3-PGA is reduced to 1 aldehyde group in 3-fosforgliseradehida (3-Pgaldehida). This reduction does not occur directly, but the carboxyl group of 3-PGA is first converted into the acid anhydride ester type 1.3-bifosfogliserat acid (1,3-bisPGA) traffic with the addition of a phosphate group from ATP final. This arises from photophosphorylation ATP and ADP are released when the 1.3-bisPGA formed, which is rapidly converted back to ATP by photophosphorylation additional reaction. Actual reducing agent is NADPH, which contributes 2 electrons. Simultaneously, Pi removed and reused to convert ADP to ATP.
In the regeneration phase, traffic which is RuBP regenerated required to react with additional traffic CO2 that diffuses into a constant basis and via the stomata. At the end of the reaction Calvin, the third ATP required for each CO2 molecule traffic tethered, is used to change the ribulose-5-phosphate to RuBP, then the cycle begins again.
Three rounds will cycle tether traffic 3 molecules of CO2 and the end product is 1,3-Pgaldehida. Most used chloroplast to form starch, traffic others brought out. This system makes the total amount of phosphate becomes constant in chloroplasts, but led to the emergence of triosafosfat in the cytosol. Trioses cytosolic phosphate used to form sucrose.
Based on how to produce glucose, the plant can be divided into C3 and C4 plants. C3 plant is a plant originating from temperate regions. These plants produce glucose to CO2 via the Calvin cycle processing, which involves the enzyme Rubisco as absorber of CO2. C3 plants requires 3 molecules of ATP to produce traffic glucose. However, ATP can be used in vain without glucose it produces. This can happen if there is photorespiration, in which the enzyme traffic Rubisco CO2 but not tie up tie up the O2. C4 plants are plants traffic that are commonly found in the tropics. This plant involves two enzymes in the processing of CO2 into glucose. Enzymes phosphophenol pyruvat carboxilase (Pepco) is an enzyme that will bind CO2 from the air and then it will be oxaloacetate. Oxaloacetate is converted into malate. Carboxylated to malate to pyruvate and CO2. Pyruvate will return to Pepco, while the CO2 will go into the Calvin cycle takes place in the bundle sheath cells and involves the enzyme RuBP. This process is called Hatch Slack cycle, which occurs in mesophyll cells. In this whole process, used 5 ATP.
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