A comparison of C3, C4 and CAM plants
C3 vs C4 vs CAM plants)
C3 plantsC3 vs C4 vs CAM plants)
1. Found in all photosynthetic plants.
2. Plants that use the cycle can be hydrophytic, mesophytic and xerophytic.
3. Photoactive Stomata
4. High rate of Photorespiration
5. Normal Leaf anatomy
6. For the synthesis of glucose molecule or 6CO2 fixation:12 NADPH and 18 ATPs are required.
7. Single CO2 fixation occurs
8. Primary CO2 atmospheric acceptor RUBP
9. First stable product 3PGA
10. First enzyme involved RUBISCO
11. Carbon dioxide compensation point: 30-70PPM

C4 Plants
1. Only in tropical plants.
2. Plants that use the cycle can be mesophytic
3. Photoactive Stomata
4. Photorespiration: less or negligible
5. Kranz anatomy
6. 12 NADPH and 30 ATPs are required.
7. Double carbon dioxide fixation
8. Atmosphere Co2 acceptor- PEP(In mesophyll cell) and Metabloic Co2 acceptor-RUBP(In bundle sheath cell)
9. First stable product OAA (Oxalo acetic acid)
10.First enzyme involved PEP Carboxylase
11. CO2 compensation point: 10PPM

CAM Plants
1. Specially in succulents growing under semi arid condition.
2. Plants that use the cycle can be xerophytic
3. Scotoactive Stomata
4. Photorespiration: least or negligible
5. Xeromorphic
6. 12 NADPH and 39 ATPs are required.
7. Double carbon dioxide fixation
8. Atmosphere Co2 acceptor- PEP(During night) and Metabloic Co2 acceptor-RUBP(during day time)
9. First stable product OAA (Oxalo acetic acid)
10.First enzyme involved PEP Carboxylase
11. CO2 compensation point: 5PPM