Question

Identify A,B $\&$ C in the above figure

• A. A - Phosphoenol pyruvate (PEP), B - Pyruvic acid, C - Oxaloacetic acid (OAA)
• B. A - OAA, B - PEP, C - Pyruvic acid
• C. A - PEP, B - OAA, C - Pyruvic Acid
• D. A - Aspartic acid, B - OAA, C - PEP

Answer 1

The correct option is C A - PEP, B - OAA, C - Pyruvic Acid

In the figure, the Hatch-Slack or C4 fixation pathway is shown. $C_4$ plants exhibit division of labour between the mesophyll and bundle sheath cells when it comes to $C{O}_2$ fixation. In these plants, phosphoenol pyruvate (PEP) acts as $C{O}_2$ acceptor, fixing it as oxaloacetatic acid (OAA). OAA is converted to malate in the mesophyll and is transported to the bundle sheath where it's converted to pyruvic acid and $C{O}_2$ that enters the Calvin cycle. Pyruvic acid is sent to the mesophyll cells where it is regenerated to PEP.