Question

$ C{{O}_{2}} $ compensation point will be

• A. higher in $ {{C}_{3}} $ plants
• B. higher in $ {{C}_{4}} $ plants
• C. equal in $ {{C}_{3}} $ and $ {{C}_{4}} $ plants
• D. zero for both type of plants.

Answer 1

Answer: (A)

: $ C{{O}_{2}} $ compensation point is the certain $ C{{O}_{2}} $ concentration at which rate of photosynthesis is just equal to rate of respiration or photosynthesis just compensates respiration or apparent photosynthesis is nil. $ C{{O}_{2}} $ compensation point is very low in $ C-4 $ plants, i.e., 0 to 5 ppm whereas high $ C{{O}_{2}} $ compensation point is found in $ C-3 $ plants, i.e. 25 to 100 ppm.