Chlorophyll-‘a’ is the primary pigment for the light reaction. What are accessory pigments? What is their role in photosynthesis?

 

 
Accessory pigments are also photosynthetic pigments. These are chlorophyll- ‘a’ xanthophyll and carotenoids. These are not directly involved in emission of excited electrons, but they help in harvesting solar radiation and pass it on to chlorophyll-a.
 
This pigment itself absorbs maximum radiation at blue and red region. So, Chlorophyll and the chief pigment of photosynthesis and others (i.e., chlorophyll-b, xanthophyll and carotinoion) are accessory pigment.