Essay On Calvin Cycle

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The C3 pathway is the Calvin cycle. The Calvin cycle has three stages. The first stage is when carbon dioxide enters into the Calvin cycle and is bonded to RuBP. This form a six carbon molecule which is further broken down create two PGA’s with three carbons. RuBP is important because of the carbon fixation that it performs. However it is more attracted to oxygen which leads to cellular respiration. In the second stage of the Calvin cycle PGA is further broken down into PGAL. In the third stage of the Calvin cycle five of the six generated molecules of glyceraldehyde get used to regenerate RuBP. The Calvin cycle requires more ATP than NADPH but both of the molecules are used. Fixed carbon is generally converted to sucrose or starch. Both are food for the plant where sucrose is readily available for the plant starch is stored and requires enzymatic activity to break down into a usable form.…show more content…
CAM plants use both of the C4 and Calvin cycle but they fix carbon dioxide at night. The process starts with the C4 pathway during the dark. Once to molecule malate is formed it stored in the vacuole as malic acid. Once light has come back the acid is broken down into RuBP. CAM plants only fix carbon at night to prevent water loss during the day. This provides a great advantage in desert regions where water may not be readily available. The adaption allows CAM plants to save water that C4 and C3 would readily lose. Some CAM plants can keep their stomata closed for longer periods of time by using carbon dioxide produced through respiration. This allows for a very minimal loss of water in extreme drought conditions. The CAM plants only perform carbon fixation at night and wait for sunlight to continue the process of photosynthesis. The fixation of carbon dioxide produced through respiration seems to be unique to these plants as well. CAM plants are best suited to arid
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