Question

With reference to factors affecting the rate of photosynthesis, which of the following statements is not correct.

• A. Tomato is a greenhouse crop which can be grown in $C{O}_2$- enriched atmosphere for higher yield.
• B. $C_3$ plants respond to higher temperatures with enhanced photosynthesis while $C_4$ plants have much lower temperature optimum.
• C. Light saturation for $C{O}_2$ fixation occurs at $10\%$ of full sunlight.
• D. Increasing atmospheric $C{O}_2$ concentration up to $0.05\%$ can enhance $C{O}_2$ fixation.

Answer 1

The correct option is B $C_3$ plants respond to higher temperatures with enhanced photosynthesis while $C_4$ plants have much lower temperature optimum.

Incorrect statement

$C_3$ plants respond to higher temperatures with enhanced photosynthesis while $C_4$ plants have much lower temperature optimum.

Elaboration

$C_4$ plants have a higher temperature maximum compared to $C_3$ plants. They respond to higher temperatures much efficiently than the $C_3$ plants. This is because these plants are adapted to the dry, high temperature conditions with the help of the $C_4$ pathway. Hence, the statement is incorrect.


Final answer

(B) $C_3$ plants respond to higher temperatures with enhanced photosynthesis while $C_4$ plants have much lower temperature optimum