Chlorophyll and absorption of light
3.8.4 Outline the differences in absorption of red, blue and green light by chlorophyll.
The absorption of light by chlorophyll can be explained based on units of light, either called a photon or quantum of light. The energy that photons carry depends on their wavelength; the shorter the wavelength the greater the energy. There are various types of chlorophyll in chloroplasts, each with various light absorbing properties. But in general, all chlorophyll can absorb, most effectively, in the red and blue part of the light spectrum. Green light is the least effective wavelength absorbed, and for this reason is why most plants appear green to the human eye. Plants grown under green light have a lower rate of photosynthesis than any other color. Below is a diagram of the absorption rate of visible light by chlorophyll (Figure 10).