Photosynthesis

Plants would not be able to perform photosynthesis without photosynthetic pigments.  These are colorful compounds that are very similar to solar panels.  Solar panels absorb light and convert it to electrical energy.  Photosynthetic pigments act in a similar way. They absorb only certain wavelengths, which the chloroplasts then use to begin photosynthesis.  The wavelengths that plants do not use are reflected, which is why the leaves of plants appear green.  The wavelength of green light, 495-570nm, is not used by the plant.  The same principle is applied to any other colorful object.  The colors that we see are really the light with wavelengths that those objects do not absorb.  

 

Pigments are very specific as to what wavelengths of light they absorb.  For this reason, plants must produce a large number of different pigments.  Chlorophyl a makes up the majority of the chloroplasts' pigments.  It absorbs blue-green light.  Chlorophyl b absorbs yellow-green light.  In addition to chlorophyll a, there are multiple secondary pigments that absorb different wavelengths of light.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The job of accesory pigments is to increase the range of wavelengths that the plant can absorb and therefore use for photosynthesis. These accesory pigments can be thought of as background singers for a lead singer.  Although the lead singer, chlorophyll a, does most of the work, the background singers enhance the performance.