| Conditions | C4 plants | C3 plants |
| (1) CO2 fixation rate under light conditions | High | Low |
| (2) Whether Photorespiration is present at low light intensities | Negligible | High |
| (3) Whether Photorespiration is present at high light intensities | Negligible | High |
| (4) Whether Photorespiration would be present at low CO2 concentration | Negligible | High |
| (5) Whether Photorespiration would be present at high CO2 concentration | Negligible | High |
| (6) Optimum Temperature | 30–40°C | 20–25°C |
| 7) Primary acceptor of CO2 | PEPA | RUBP |
| (8) Primary product | OAA(4C) | PGA(3C) |
| (9) Does the plant have RUBISCO? | In bundle sheath cells only | Yes |
| (10) Does the plant have PEP case ? | Yes | No |
