An alternative, very efficient
metabolic pathway used by plants living in areas with low levels of
carbon dioxide. They use this pathway to convert carbon dioxide into a form usable during
photosynthesis. Plants in environments with normal
carbon dioxide concentrations use the
Calvin cycle instead of this pathway, which is also called the
C4 cycle.
From the BioTech Dictionary at http://biotech.icmb.utexas.edu/. For further information see the BioTech homenode.