The main photosynthetic pigment in chloroplasts is the blue-green chlorophyll a. Accessory pigments are yellow-green chlorophyll b, yellow-brown xanthophylls, orange carotenoids and phaeophytin which is a grey-brown pigment.The role of the pigments is to capture light energy by electron excitation. When light is absorbed by a pigment its electrons are excited to a higher energy level. The electrons can then take part in redox reactions transferring the light energy to other reactions. Different pigments absorb light of different wavelengths ensuring the plant absorbs as much light as possible. Chlorophylls a and b absorb red and blue light and reflect green light, so they appear green.