Question

What are some enzymatic challenges used by plants to evolve under increasing co2 concentrations and where does each carbon cycle pathway give benefit to the plant?

Answer 1

Carbon dioxide level are very important in photosynthesis ,insufficient carbon dioxide available for fixing in the calvi cycle maens that the reaction cannot proceed at maximum rate .in such situation co2 is limiting factor, changes in the level of co2 may effect the photosynthesis level.but if the co2 is increased than plant use different pathways for evolving and fixing co2.such type of mechanism are calvin cycle or c3 cycle and hatch and slack cycle or c4 cycle   .. calvin cycle-it operate in all plants ,the optimal temperature for the operation of this cycle is 10-25celcius,and the primary acceptor of co2 is RuBp ,a 5 carbon compound,it is less energy-expensive than c4 pathways whereas in hatch and slack cycle(c4) -it operate only in c4 plants,the optimum temperature to operate this cycle is 30-45C ,the primary acceptor of co2 is PEP a3 carbon compound ,the first compound is formed is oxaloacetate ,a 4 carbon compound.