Read the following statements regarding the enzyme RuBisCO: (I) It is the most abundant protein in the whole of the biosphere. (II) Its binding to CO ₂ and O ₂ is competitive. (III) It has a much greater affinity for O ₂ than for CO ₂ . (IV) It catalyzes the conversion of RuBP to oxaloacetic acid (OAA). How many of the above statements are correct?

Step-by-step solution

Statement (I) is correct as RuBisCO is the most abundant protein in the whole of the biosphere. Statement (II) is correct because the active site of RuBisCO can bind to both CO ₂ and O ₂ , and their binding is competitive. Statement (III) is incorrect because RuBisCO has a much greater affinity for CO ₂ than for O ₂ . It is the relative concentration of these gases that determines which will bind to the enzyme. Statement (IV) is incorrect because RuBisCO catalyzes the carboxylation of RuBP to form two molecules of