The upcoming discussion will update you about the differences between C3 plants and C4 Plants.
Difference # C3 Plants (Calvin Cycle):
1. Optimum temperature for photosynthesis is 10-25°C.
2. Atmospheric concentration of oxygen (21%) reduces the rate of photosynthesis which is optimum at 2-4% O2 concentration.
3. Saturation point is reached at 10—70% of full sunlight.
4. Rate of net photosynthesis are optimum sunlight is 15-35 mg CO2/dm2/hr.
5. The leaves do not possess Kranz anatomy.
6. Chloroplasts do not have peripheral reticulum.
7. Chloroplasts are of one type (monomorphic).
8. Bundle sheath cells usually do not contain chloroplasts.
9. In higher plants operating C3 cycle, the chloroplasts are all granal.
10. Ribulose bi-phosphate is the first acceptor of CO2
11. Phosphoglyceric acid is the first product.
12. The plants operate only Calvin cycle.
13. CO2 compensation point is 25-100 ppm.
14. Mesophyll cells perform complete photosynthesis.
15. The rate of carbon assimilation is slow.
16. The plants are unable to perform photosynthesis at very low CO2 concentration (say 10-50 ppm).
17. Rate of photorespiration is quite high.
18. At low temperature, C3 plants are more efficient while at high temperature their photosynthetic activity is comparatively reduced.
19. The cycle operates in all plants.
20. The plants are adapted to all types of climates.
21. C3 plants usually cannot tolerate saline conditions.
22. Fixation of one molecule of CO2 uses 3ATP and 2NADPH.
23. C3 plants usually perform photosynthesis only when stomata are open.
24. Photosynthesis stops under conditions of water stress.
Difference # C4 Plants (Hatch Slack Cycle):
1. Optimum temperature is 30-45°C.
2. There is no such effect.
3. Saturation point is not reached even at full sunlight.
4. Rate of net photosynthesis at full sunlight is 40-80 mgCO2/dm2/hr.
5. The leaves have Kranz anatomy.
6. Chloroplasts have peripheral reticulum.
7. There are two types of chloroplasts (dimorphic).
8. Bundle sheath cells possess prominent chloroplasts.
9. There are two types of chloroplasts, granal in mesophyll cells and agranal in bundle sheath cells.
10. Phosphoenol pyruvate is the first acceptor of CO2, while ribulose biphosphate is the second acceptor.
11. Oxalo-acetic acid is the first product.
12. Plants operate a dicarboxylie acid cycle in addition to Calvin cycle.
13. CO2 compensation point is 0-10 ppm.
14. Mesophyll cells perform only initial fixation.
15. The rate of carbon assimilation is quite rapid.
16. Photosynthesis continues even at very low CO2 concentration of 10-50 ppm.
17. Rate of photorespiration is negligible.
18. C4 plants are Jess efficient than C, plants at low temperature but they have a higher net assimilation at high temperature.
19. The cycle is found only in some plants.
20. The plants are adapted to tropical climate.
21. C4 plants can tolerate halophytic conditions.
22. Fixation of one molecule of CO2 requires 5ATP and 2NADPH.
23. C4 plants perform photosynthesis even when stomata are closed (from CO2 produced in respiration).
24. Photosynthesis is appreciable even under conditions of water stress.