Question

Assertion :Amount of organic matter synthesised by producers per unit time and per unit area during the process of photosynthesis is referred to as net primary productivity. Reason: Primary productivity is usually high and sustained throughout the year in temperate areas due to abundance of sunlight.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is D Both Assertion and Reason are incorrect

The total amount of organic matter synthesized by producers per unit time and per unit area, in the process of photosynthesis is called as gross primary productivity(GPP). Primary productivity is high and sustained throughout the year in the tropical area while it is limited in temperate area by cold climate and small growing period. Maximum sunlight is available in tropics whereas poles receive minimum sunlight. Due to this, photosynthesis is maximum and net primary productivity(NPP) is highest (>20 t ha−1 year−1) in tropics against average (8 t ha−1 year−1) in temperate forests.

So, the correct answer is 'Both Assertion and Reason are incorrect'.