Red Drop and Emerson Enhancement Effect Experiment Summary

Emerson Red Drop and Enhancement Effect

•The rate of photosynthesis is measured as the number of O2 molecules produced per quantum of light absorbed

• Robert Emerson et al (1958): Experimental material Chlorella

• Studying rate of photosynthesis at different wavelengths of light (390-760 nm)

• Monochromatic light of different wavelength is used and rate of photosynthesis is measured

• The sudden fall in photosynthetic yield in the far red region (greater than 680 nm) compared to the red region of the electromagnetic spectrum is called “Emersons red drop”

• The increase in photosynthetic yield by the combined effect of red (680 nm) and far red light (700 nm) is called Emerson enhancement effect or Emerson effect.

• This work provide experimental evidence for the presence of two photo systems-PS I & PS II