accessory pigment

noun

: any of various pigments (such as carotenoids and phycobilins) that are found in photosynthetic cells and absorb light of wavelengths not absorbed by chlorophyll a

Algae at deep regions receive mostly green and blue light and must have special accessory pigments capable of absorbing these wavelengths efficiently.

—James D. Mauseth, Botany: An Introduction to Plant Biology, 2009

Note: The light energy absorbed by accessory pigments must be transferred to chlorophyll a before it can be used in photosynthesis.

Word History

First Known Use

circa 1893, in the meaning defined above

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