Photorespiration in C3 plants occurs when RuBisCO acts as an oxygenase instead of a carboxylase. This process primarily takes place in which organelles? MCQ with Answer and Explanation

Photorespiration in C3 plants occurs when RuBisCO acts as an oxygenase instead of a carboxylase. This process primarily takes place in which organelles?
A. Chloroplast, Mitochondria, and Peroxisome
B. Mitochondria and Golgi apparatus
C. Peroxisome and Lysosome
D. Chloroplast and Nucleus
Answer: Option A
Solution (By JKSSB Mock Tests)
Photorespiration is a wasteful pathway that occurs when RuBisCO fixes O2 instead of CO2, producing phosphoglycolate. This 2-carbon compound is metabolized through a complex pathway involving three organelles: it is processed in the peroxisome, then the mitochondria, and finally returns to the chloroplast. This process consumes ATP and releases CO2 without producing any sugar.

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