Question

With reference to factors affecting the rate of photosynthesis, which of the following statement is not correct ?

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

Answer 1

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

In $C_3$ plants, photosynthesis decreases with increase in temperature due to increase in photorespiration.

$C_4$ plants tolerate higher temperatures and show a response to high light intensities. They lack a process called photorespiration and have greater productivity at high optimum temperature.