Question

Which one is wrong with respect to photorespiration?

• A. It occurs in chloroplasts
• B. It occurs in day time only
• C. It is characteristic of $C_4$ plants
• D. It is characteristic of $C_3$ plants

Answer 1

The correct option is C It is characteristic of $C_4$ plants

Photorespiration: It is inhibition of photosynthesis by high O${}_2$ level was termed as Warburg effect. However, the inhibition was observed mostly in C${}_3$ plants. The C${}_4$ plants were hardly affected by varying O${}_2$ concentrations. This is because the C4 plants have a spatial separation in the form of mesophyll cells and bundle sheath cells, wherein the CO${}_2$ is accepted by PEP rather than RUBP.

The process occurs in chloroplast, peroxisome and mitochondria.

It is rather a wasteful process.

Hence, the correct answer is 'It is characteristic of C${}_4$ plants'.