Table 1. Four Phases of the CAM Cycle
PhaseDescription
IStomata open during the dark period and nocturnal CO2 assimilation by PEPC
IITransition phase between dark and light periods with a peak in CO2 uptake and fixation of CO2 by Rubisco
IIIStomata closed during the light period and fixation of CO2 that is released by decarboxylation of carboxylic acids
IVTransition phase between light and dark periods with direct Rubisco-mediated fixation of CO2