Whats the difference between C3, C4, and CAM plant?
C3, C4, and CAM plants all carry out the same photosynthetic functions. They all have light-dependent reactions and the Calvin-Benson cycle. The major difference in C4 and CAM plants is when and where the carbon fixation initially occurs. In C3 plants, the light reactions occur in the palisade mesophyll cells. Carbon fixation also occurs in these cells during the Calvin-Benson cycle. An enzyme called ribulose bisphosphate carboxylase oxygenase (rubisco for short) fixes incoming carbon dioxide molecules into three carbon molecules called glyceraldehyde-3-phosphate (G3P). The G3P goes thorough a series of reductions to form carbohydrate molecules. Because these biochemical pathways are virtually identical in all three types of plants, I won’t elaborate on them. C4 plants typically live in warmer, drier climates than normal C3 plants can withstand. When the outside air is hot and dry, C3 plants must close their stomata or they risk losing too much water via transpiration. But closing the
