2023 Manipur Photosynthesis in Higher PlantsRuBisCO and photorespiration in C4 plants Medium Question 21 of 91 in Photosynthesis in Higher Plants

Given below are two statements: Statement I: RuBisCO is the most abundant enzyme in the world. Statement II: Photorespiration does not occur in C4 plants. In the light of the above statements, choose the most appropriate answer from the options given below:

A Statement I is correct but Statement II is incorrect
B Statement I is incorrect but Statement II is correct
C Both Statement I and Statement II are correct
D Both Statement I and Statement II are incorrect

The answer is C.

Solution

RuBisCO (ribulose bisphosphate carboxylase-oxygenase) is indeed considered the most abundant enzyme in the world, so Statement I is correct. In C4 plants, RuBisCO is localised in the bundle sheath cells where $CO_2$ concentration is kept high, effectively suppressing its oxygenase activity, so photorespiration does not occur (or is negligible) in C4 plants — Statement II is also correct.

Concept RuBisCO and photorespiration in C4 plants

Photosynthesis in Higher Plants in past papers

91 questions from this chapter have appeared across 26 exam years.