Q. With reference to factors affecting the rate of photosynthesis which of the following statements is not correct :
(a) Increasing atmospheric CO2 concentration up to 0.05% can enhance CO2 fixation rate
(b) C3 plants respond to higher temperatures with enhanced photosynthesis while C4 plants have much lower temperature optimum
(c) Tomato is a greenhouse crop that can be grown in CO2 – enriched atmosphere for a higher yield
(d) Light saturation for CO2 fixation occurs at 10% of full sunlight
Solution :
Correct option : B Explanation of the correct option: 1. C3 plants have the RuBisCo enzyme which gets activated at higher carbon dioxide concentration. 2.C4 plants have PEP as a major CO2 acceptor. 3. Photosynthetic activity is mostly affected by enzymes rather than temperatures. 4. High temperature leads to the destruction of photosynthetic pigments. 5.So, C3 plants will not respond to higher temperatures with enhanced photosynthesis.