NEET2016BotanyPhotosynthesis in Higher PlantsActual
Photosynthesis in C ₄ plants is relatively less limited by atmospheric CO ₂ levels because
Options
- Athere is effective pumping of CO ₂ into bundle sheath cells
- BRuBisCO in C ₄ plants has higher affinity for CO ₂
- Csix carbon acids are the primary initial CO ₂ fixation products
- Dthe primary fixation of CO ₂ is mediated via PEP carboxylase.
Correct answer
D. the primary fixation of CO ₂ is mediated via PEP carboxylase.
Step-by-step solution
CO ₂ acceptor molecule in C ₄ plants is phosphoenol pyruvate (PEP). C ₄ plants are more efficient in picking up CO ₂ even when it is found in low concentration because of high affinity of PEP. PEP carboxylase (PEPcase) is the key enzyme which catalyses the primary fixation of CO ₂ .