Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
Rubisco enzyme can act both as carboxylase and as oxygenase. In C4 cycle it functions as
BiologyPhotosynthesis in Higher PlantsNEET
Options:
  • A Oxygenase only
  • B Carboxylase only
  • C Mainly carboxylase activity minimizing oxygenase.
  • D Oxygenase but sometimes as carboxylase
Solution:
2861 Upvotes Verified Answer
The correct answer is: Mainly carboxylase activity minimizing oxygenase.
In C4 plants photorespiration does not occur. This is because they have a mechanism that increases the concentration of CO2 at the enzyme site. This takes place when the C4 acid from the mesophyll is broken down in the bundle sheath cells to release CO2 – this results in increasing the intracellular concentration of CO2. In turn, this ensures that the RuBisCO functions as a carboxylase minimizing the oxygenase activity.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.