How do plants absorb carbon dioxide?
Primarily through the stromata, pores on the epidermis of the photosynthesizing parts of plants. These pores, however, tend to increase water loss when open. So when water is in short suppy, the stomata tend to close. The CO2 bonds with ribulose bisphosphate (RuBisCO), a 5 carbon compound to form two 3 carbon compounds. This is part of the Calvin cycle. In highly arid habitats, though, this method simply isn’t good enough. There are two other methods, called C4 and CAM. These methods tend to be much more efficient with water useage. CAM fixes carbon at night when water loss will be minimal. C4 plants fix carbon to other intermediate compounds then transport it to the (RuBisCO).
