Biology · PHOTOSYNTHESIS IN HIGHER PLANTS

Which of the following correctly describes the comparative temperature optima for C₃ and C₄ plants?

1. A
   C₃ plants have a higher temperature optimum (30–40°C) than C₄ plants (20–25°C).
2. B
   Both C₃ and C₄ plants have identical optimum temperatures because dark reactions are enzymatic.
3. C
   C₄ plants respond to higher temperatures and have a higher temperature optimum (30–40°C or above), whereas C₃ plants have a lower temperature optimum (20–25°C).
4. D
   C₄ plants show temperature sensitivity only during the photolysis of water in mesophyll cells.