Question

Describe briefly the effect of light, $C{O}_2$ concentration, and temperature on the rate of photosynthesis.

Answer 1

Light is one of the major factors affecting photosynthesis. Photosynthesis cannot occur in the dark and the source of light for the plants is sunlight. The intensity of light and quality of light influence rate of photosynthesis. Light becomes a limiting factor in low intensity because no matter how much water or CO2 is present, without light photosynthesis cannot occur.

Plants take in carbon dioxide from the air. But, since the amount of CO2 in the air is very less, it acts as a limiting factor for photosynthesis. It is seen that, when light and temperature are not the limiting factors, increasing CO2 concentration leads to an increase in the rate of photosynthesis. All biological and biochemical processes that they occur best in a certain optimum range of temperature. It is observed that, when CO2 and light are not limiting factors, the rate of photosynthesis increases with increase in temperatures till the optimum level for that plant.