Photorespiration : (a) It is a threat to plants although it occurs in angiosperms because it has some disadvantages.
(b) No energy rich compound is produced in this process.
(c) Half of the photosynthetically fixed CO2 may be lost by photorespiration.
(d) Moreover it is a loss to the net productivity of green and C3 plants
(e) To overcome the photorespiratory loses in angiosperms like sugarcane, they have developed
an additional cycle called as C4 pathway or Hatch Slack pathway.
(f) C4 pathway requires 30 ATP molecules (more energy).