Question

If the temperature is increased above 35^oC,

• A. Rate of decline of respiration will be earlier than that of photosynthesis.
• B. The rate of decline of photosynthesis will be earlier than the decline of respiration.
• C. Both will decline simultaneously.
• D. Both do not show any fixed pattern.

Answer 1

The correct option is B

The rate of decline of photosynthesis will be earlier than the decline of respiration.

The correct option is B.

Explanation of the correct option:

1. The intensity of light, carbon dioxide content, and temperature are all factors that influence photosynthesis.
2. The rate of photosynthesis is optimum at temperatures ranging from 25^oC to 35^oC since enzymes stop operating at temperatures around 0^oC and get denatured at very high temperatures.
3. As a result, increasing the temperature over 35^oC will result in a decrease in photosynthesis rate owing to the denaturation of carbon-fixing enzymes.
4. Similarly, at extremely high temperatures, the rate of respiration decreases dramatically.

Final answer: If the temperature is increased above 35^oC, the rate of decline of photosynthesis will be earlier than the decline of respiration.