Question

The first product of $ C{{O}_{2}} $ fixation in Hatch and Slack cycle in plants is:

• A. formation of bundle sheath cells
• B. formation of oxaloacetate by carboxylation of phosphoenol pyruvate (PEP) in the mesophyll cells
• C. formation of phosphoglyceric acid in mesophyll cells
• D. formation of oxaloacetate by carboxylation of phosphoenol pyruvate (PEP) in bundle sheath cells

Answer 1

Answer: (B)

Hatch and Slack cycle is present in $ {{C}_{4}} $ plants in which initial fixation of carbon dioxide $ (C{{O}_{2}}) $ occurs in mesophyll cells phosphoenol pyruvate (PEP) is the primary acceptor of $ C{{O}_{2}} $ which combines to $ C{{O}_{2}} $ form four carbon compounds oxaloacetic acid as a result of carboxylation $ PEP+C{{O}_{2}}+{{H}_{2}}O\xrightarrow[\begin{smallmatrix} Carboxylase \\ Oxalso-\,acetic\,acid \end{smallmatrix}]{PEP} $