8. Following  are certain   statements regarding photorespiration pathway in plants:
(A) The first two-carbon (2C) compound synthesized by the action of Rubisco in the chloroplast is glycolate
(B) Glycolate exits the   chloroplast and enters peroxisomes.
(C) Glycolate that is synthesized during C2 cycle ente the chloroplast from mitochondria.
(D)Glycine is transported from peroxisornes mitochondria.
Which one of the following combinations is INCORRECT?
(1) A and B only            (2) A and C only
(3) B,C and D                (4) A, C and D

Introduction

Photorespiration is a complex metabolic pathway that involves multiple organelles for the recycling of photorespiratory intermediates. Knowing how metabolites move between these compartments is essential for understanding this key plant physiological process.

Explanation of Each Statement

(A) The first two-carbon (2C) compound synthesized by the action of Rubisco in the chloroplast is glycolate.

• Correct. Rubisco’s oxygenase activity produces 2-phosphoglycolate, which is dephosphorylated to glycolate, the first 2-carbon product of photorespiration.

(B) Glycolate exits the chloroplast and enters peroxisomes.

• Correct. Glycolate is transported out of the chloroplast to peroxisomes for oxidation to glyoxylate.

(C) Glycolate that is synthesized during the C2 cycle enters the chloroplast from mitochondria.

• Incorrect. Glycolate is produced in chloroplasts, not mitochondria, and it exits chloroplasts for peroxisomes.

(D) Glycine is transported from peroxisomes to mitochondria.

• Incorrect. Glycine is transported from mitochondria to peroxisomes during photorespiration.

Why Option (3) B, C and D Are Incorrect

Statements C and D incorrectly assign metabolite transport directions and organelles involved:

• Glycolate does not enter the chloroplast from mitochondria.

• Glycine is transported from mitochondria to peroxisomes, not the reverse.

Statement B is correct, so its inclusion here as ‘incorrect’ suggests the option labeling B is also part of the incorrect statements, making this combination the only one that correctly groups all wrong statements.