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Chlorophyll is the primary pigment in plants; it is a chlorin that absorbs blue and red wavelengths of light while reflecting a majority of green. It is the presence and relative abundance of chlorophyll that gives plants their green color. All land plants and green algae possess two forms of this pigment: chlorophyll a and chlorophyll b.
Like plants, the cyanobacteria use water as an electron donor for photosynthesis and therefore liberate oxygen; they also use chlorophyll as a pigment.In addition, most cyanobacteria use phycobiliproteins, water-soluble pigments which occur in the cytoplasm of the chloroplast, to capture light energy and pass it on to the chlorophylls.
Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. [2] Its name is derived from the Greek words χλωρός (khloros, "pale green") and φύλλον (phyllon, "leaf"). [3] Chlorophyll allows plants to absorb energy from light.
Pigments for sale at a market stall in Goa, India. A pigment is a powder used to add color or change visual appearance. Pigments are completely or nearly insoluble and chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use.
Anthocyanins may be used as pH indicators because their color changes with pH; they are red or pink in acidic solutions (pH < 7), purple in neutral solutions (pH ≈ 7), greenish-yellow in alkaline solutions (pH > 7), and colorless in very alkaline solutions, where the pigment is completely reduced. [57]
When leaves change color in the autumn, it is due to the loss of green chlorophyll, which unmasks preexisting carotenoids. In this case, relatively little new carotenoid is produced—the change in plastid pigments associated with leaf senescence is somewhat different from the active conversion to chromoplasts observed in fruit and flowers.
In higher plants, there are three carotenoid pigments that are active in the xanthophyll cycle: violaxanthin, antheraxanthin, and zeaxanthin. During light stress, violaxanthin is converted, i.e. reduced, to zeaxanthin via the intermediate antheraxanthin, which plays a direct photoprotective role acting as a lipid-protective anti-oxidant and by ...
Anthocyanidins are common plant pigments, the aglycones of anthocyanins. They are based on the flavylium cation , [ 1 ] an oxonium ion , with various groups substituted for its hydrogen atoms. They generally change color from red through purple, blue, and bluish green as a function of pH .