Class 11 NEET Biology Photosynthesis in Higher Plants

(b) : The Calvin cycle is also known as C3 cycle because CO2 reduction is cyclic process and first stable product in this cycle is a 3 -C compound (i.e., 3 -phosphoglyceric acid or 3 -PGA). In this cycle, CO2 acceptor molecule is RuBP or RuDP (i.e., Ribulose 1, 5-biphosphate or Ribulose 1,5 -diphosphate ). There occurs covalent bonding of CO2 to RuBP and the enzyme catalyzing this reaction is RuBP-carboxylase\/oxygenase (RuBisCO).