Important Difference Between C3 Plants And C4 Plants

Difference Between C3 Plants and C4 Plants:

The following are the points of difference between C₃ plants and C₄ plants–

C₃ plants	C₄ plants
They are mainly temperate plants.	They are mainly tropical plants.
They operate only the Calvin cycle.	They operate the Calvin cycle as well as the Hatch and Slack pathway.
The optimum temperature for photosynthesis is 20°-25°C.	The optimum temperature for photosynthesis is 30°-45°C.
The transpiration ratio is 500-1000.	The transpiration ratio is 250-350.
CO₂ fixation takes place in mesophyll cells only.	CO₂ fixation takes place in mesophyll and bundle sheath.
Chloroplasts are granal (one type).	Chloroplasts are of two types (granal and agranal).
Chloroplasts are without peripheral reticulum.	Chloroplasts posses a peripheral reticulum.
Leaves do not show kranz anatomy.	Leaves show kranz anatomy.
They perform photorespiration.	Photorespiration is not detectable.
The first acceptor of CO₂ is RuBP.	The first acceptor of CO₂ is PEP while the second acceptor is RuBP.
The first stable compound after carboxylation is PGA (phosphoglyceric acid).	The first stable compound after carboxylation is OAA (oxaloacetic acid).
PGA is reduced in the chloroplasts where it is formed.	PGA is formed in bundle sheath cells but is reduced in mesophyll cells.
The carboxylase enzyme is Rubisco.	The carboxylase enzyme is PEP carboxylase and Rubisco.
18 ATPs used to synthesize one glucose.	Consumes 30 ATPs to produce one glucose.
CO₂ compensation point lies between 50-100 ppm.	CO₂ compensation point lies between 0-10 ppm.
Example: Paddy, Wheat, Potato, and so on.	Example: Sugar cane, Maize, Sorghum, Amaranthus, and so on.