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in cold-blooded vertebrates, pigment cells containing melanin granules; the last stage in the differentiation of melanocytes.
Melanophores are large dendritic cells that respond to changes in light or to the pituitary melanocyte-stimulating hormone by changing color. This change reflects the alteration of the dispersion of the pigment granules in the cytoplasm. Melanophores cannot divide, migrate, or synthesize tyrosinase, the specific enzyme necessary for melanin synthesis. Together with other chrotnatophores, they make up part of a system responsible for rapid changes in skin color in a number of animals, including many fishes, amphibians, and chameleons.