Melanocytes (1) are special cells which produce the brown skin color (melanin) in the basal cell layer of the epidermis. Melanocytes form long, finger-like protuberances (dendrites) (2), which grow into and through the neighboring keratinocytes (3). Under the influence of UV light a biosynthesis of melanin occurs in the melanosomes. These are particular cell components of the melanocytes which are filling up more and more with melanin while they move further to the periphery of the cell and into the dendrites, thus filling up the originally colorless skin cells (keratinocytes) with brown pigments.

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