Xanthophylls represent a class of _________ pigments
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Answer: A. Yellow
Explanation
Xanthophylls are organic accessory pigments that contain oxygen atoms in their molecular structures. Their chemical properties absorb certain wavelengths of light while reflecting yellow wavelengths. This distinct optical characteristic classifies them definitively as yellow photosynthetic pigments. Xanthophylls belong to a broader class of natural tetraterpenoid compounds known as carotenoids. They are found abundantly in the leaves of most green plants during the growing season. These pigments help protect photosynthetic machinery from damage caused by excessive light energy.
Autumn foliage turns yellow when chlorophyll degrades and reveals the underlying persistent xanthophyll pigments. Dietary xanthophylls play important roles in human eye health by filtering harmful blue light. Plant physiologists study photosynthetic pigments to understand energy conversion efficiency in flora. Red pigments in plants are typically associated with anthocyanins rather than standard xanthophylls. Orange coloration in carrots and similar vegetables is primarily due to different carotenoid pigments. Green photosynthetic pigmentation is caused by chlorophyll molecules rather than xanthophyll compounds.
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