Question

The rate limiting step in photosynthesis is

• A. Light reaction
• B. Dark reaction
• C. Both (A) and (B)
• D. None of the above

Answer 1

The correct option is B Dark reaction

• In chemical kinetics, the overall rate of a reaction is often approximately determined by the slowest step, known as the rate-determining step (RDS) or rate-limiting step.
• The rate-limiting step in photosynthesis is a dark reaction.
• In dark reaction, two types of cyclic reaction occur.
• The carbon dioxide is fixed to energy-rich carbohydrates using ATP and the assimilatory power NADPH2 of light reaction.
• Hence, The rate-limiting step in photosynthesis is Dark reaction.
• So, the correct answer is 'Dark reaction'.