A pigment is any substance that absorbs light. The color we see comes from the wavelengths of light that reflect. Chlorophyll, the green pigment common to all photosynthetic cells, absorbs all wavelengths of visible light except green. The green reflects back to our eyes. Black pigments absorb all of the visible wavelengths that strike them. White pigments reflect all or almost all of the wavelengths striking them. Each color has a unique mix of reflected and absorbed wavelengths.
Chlorophyll is a complex molecule. A number of slightly modified versions of chlorophyll exist. All photosynthetic organisms (plants, algae, prochlorobacteria, and cyanobacteria) have the form known as chlorophyll a. These organisms also contain other pigment molecules known as accessory pigments (see Table). Accessory pigments absorb energy not absorbed by chlorophyll a. Chlorophyll b, xanthocyanin (a reddish pigment found in coleus leaves), and beta-carotene (the yellow-colored pigment found in carrots) are examples of accessory pigments. …show more content…
Taxonomic Group Photosynthetic Pigments
Cyanobacteria chlorophyll a, chlorophyll c, phycocyanin, phycoerythrin
Chloroxybacteria (Prochloron) chlorophyll a, chlorophyll b
Green Algae (Chlorophyta) chlorophyll a, chlorophyll b, carotenoids
Red Algae (Rhodophyta) chlorophyll a, phycocyanin, phycoerythrin, phycobilins
Brown Algae (Phaeophyta) chlorophyll a, chlorophyll c, fucoxanthin and other carotenoids
Golden-brown Algae (Chrysophyta) chlorophyll a, chlorophyll c, fucoxanthin and other