Question

What will be the effect of intermittent light on photosynthesis?

• A. It will increase.
• B. It will decrease.
• C. Will not be effected.
• D. Process will stop.

Answer 1

The correct option is A It will increase.

Photosynthesis is the process of carbon fixation, which mainly takes place in two steps, light reaction, and dark reaction. ATP and NADPH${}_2$ produced in the light reaction are utilized for carbon fixation during the dark reaction. Light reaction is much faster than dark reaction, so in continuous light there is an accumulation of ATP and NADPH${}_2$ and hence reduction in the rate of photosynthesis. But in discontinuous light (intermittent light), ATP and NADPH${}_2$ formed in light are fully consumed during dark reaction in the reduction of CO${}_2$ to carbohydrates, so the rate of photosynthesis increases.

So, the correct answer is 'It will increase.'