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MODEL PAPER 10 — BIOLOGY STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 ScienceBIOLOGYMODEL PAPER 102 Marks
Question
Why does a green plant start evolving $CO _2$, instead of $O _2$. on a hot summer day? Explain.
✓

Answer

It is due to photorespiration. With an increase in temperatures as on a hot summer day, the affinity of RuBP carboxylase for $CO _2$ reduces. It increases for $O_2$  Therefore, more and more photosynthetically fixed carbon is lost by photorespiration.

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