Question

Discovery of Emerson effect has clearly shown the existence of

• A. Two distinct photochemical reaction or processes
• B. Light and dark reactions in photosynthesis
• C. Photophosphorylation
• D. Photorespiration

Answer 1

Answer: (A)

Two distinct photochemical reaction or processes

Photosynthesis depends on upon the intensity of light which is incident on a plant within a particular range of frequency. The Emerson effect is the increase in the rate of photosynthesis after exposure to light of wavelength 670 nm far red light and 700 nm, red light respectively. When simultaneously exposed to the light of both wavelengths, the rate of photosynthesis is far higher than the sum of the red light and far red light photosynthesis rates. The effect was early evidence that photosystems processing different wavelengths cooperate in photosynthesis.

So, the correct answer is option A.