How do C4 plants operate with more efficiency carbon fixation in the Calvin cycle?
C4 Plants Over 8000 species of angiosperms, scattered among 18 different families, have developed adaptations which minimize the losses to photorespiration. They all use a supplementary method of CO2 uptake which forms a 4-carbon molecule instead of the two 3-carbon molecules of the Calvin cycle. Hence these plants are called C4 plants. (Plants that have only the Calvin cycle are thus C3 plants.) Some C4 plants — called CAM plants — separate their C3 and C4 cycles by time. CAM plants are discussed below. Other C4 plants have structural changes in their leaf anatomy so that their C4 and C3 pathways are separated in different parts of the leaf with RUBISCO sequestered where the CO2 level is high; the O2 level low. This reduces photorespiration – the binding of oxygen to RUBISCO. (details in link).
