Question

Red drop discovered by Emerson is due to disruption of photochemical activity of

Answer 1

Red drop effect
Red drop effect is decrease in the quantum yield (defined as the number of oxygen molecules released per light quanta) of photosynthesis after 680 nm i.e., in the far red region of the spectrum.

Photosystem II optimally functions at 680 nm. Disruption of photochemical activity of PS II occurs when the supplied wavelength exceeds 680 nm. This is known as red drop effect.

Hence, red drop effect is caused due to disruption in photochemical activity of PS II.