Photorespiration: The excess respiration taking place in green cells in the presence of light is called photorespiration. It is also called C2 cycle because two carbon glycolic acid acts as the substrate. Three organelles, namely chloroplast, peroxisome and mitochondria are involved in photorespiration. Generally photorespiration is found in C3 plants and absent in C4 plants.
Aerobic Respiration: It takes place in the presence of oxygen and the respiratory substrate gets completely oxidised to carbon dioxide and water as end products. This type of respiration is of common occurrence and it is often used as a synonym of respiration.
Photorespiration vs Aerobic RespirationPhotorespiration
1. It takes place only in green photosynthesising cells.
2. It takes place predominantly in C3 plants.
3. It takes place only during day time in the presence of light.
4. Steps of photorespiration occur in chloroplast, peroxisome and mitochondria.
5. Saturated point is attained at high oxygen concentration.
6. The substrate used is glycolic acid.
7. It does not involve glycolysis, Krebs cycle or Electron Transport System (ETS).
8. It does not produce any usuable energy in the form of ATP; phosphorylation does not take place.
9. End products are CO2 and PGA.
10. Temperature sensitive; 25-35 0C is ideal for photorespiration.
1. It takes place in both green and non green cells.
2. It takes place in all plants.
3. It takes place both in light and dark.
4. Steps of respiration occur in cytoplasm and mitochondria.
5. Saturation point is reached at a comparatively low oxygen concentration.
6. The substrate used are usually sugars and fats.
7. It involves glycolysis, Krebs cycle or Electron Transport System (ETS).
8. It produces usuable energy in the form of ATP; oxidative phosphorylation takes place.
9. End products are carbon dioxide and water.
10. It is not temperature sensitive.