Which of the following statements about RuBisCO is true?

Question

Professor PC Thomas Classes · Answer

(b) : Carboxylation is the fixation of $\mathrm{CO}_2$ into a stable organic intermediate. It is the most crucial step of Calvin cycle where $\mathrm{CO}_2$ is utilised for the carboxylation of RuBP. This reaction is catalysed by enzyme RuBisCO which results in the formation of two molecules of 3-phosphoglyceric acid or PGA, which is the first stable product of photosynthesis. RuBisCO has high affinity for $\mathrm{CO}_2$ when the ratio of $\mathrm{CO}_2$ to $\mathrm{O}_2$ is nearly equal. At mild temperature, RuBisCO has high affinity for $\mathrm{CO}_2$ that is about 80 times higher than its affinity for oxygen. In addition, RuBisCO has higher affinity for $\mathrm{O}_2$ when temperature increases. The phenomenon of breaking up of water into hydrogen and oxygen in the illuminated chloroplasts is called photolysis or photocatalytic splitting of water. Water splitting complex is associated with the PS II, which itself is physically located on the inner surface of thylakoid membrane. There is no role of RuBisCO in photolysis of water.