Question

What is the percentage of photosynthetically active radiation (PAR), in the incident solar radiation?

Options

• 100%

• 50%

• 1-5%

• 2-10%

Answer 1

50%

Explanation:

Less than 50 per cent of incident solar radiation is photosynthetically active radiation (PAR). Plants and photosynthetic bacteria (autotrophs) fix the Sun’s radiant energy to make food from simple inorganic materials. Plants capture only 2-10 per cent of the PAR, and this small amount of energy sustains the world.