Photosynthesis in C4 plants is relatively less limited by atmospheric CO2 levels because
four carbon acids are the primary initial CO2 fixation products
the primary fixation of CO2 is mediated via PEP carboxylase
effective pumping of CO2 into bundle sheath cells
RUBISCO in CO4 plants has higher affinity for CO2
B.
the primary fixation of CO2 is mediated via PEP carboxylase
The fixation of CO2 in C4 plants takes place in two places and by two different organic
compounds. Phosphoenol pyruvate (PEP) is found in mesophyll cells which primarily fixes atmospheric CO2 into oxaloaceticacid (4C).
RUBISCO is present in bundlesheath cells where final fixation of CO2 in hexose sugars takes place. CO2 is primarily fixed by PEP carboxylase because this enzyme has greater affinity to CO2 than RUBISCO.
