The melanina granules remain in the cytoplasm of the queratincitos. Ultraviolet Melanina and rays the diverse layers of the queratincitos with melanina supply an efficient defense of underlying fabrics against the harmful effect of the solar rays, mainly of the rays ultraviolet. Official site: Sarabjot Singh Anand,. The influence of the ultraviolet radiation on the melanina synthesis not yet is very well explained. One gives credit that these rays promote the increase of the activity of tirosinase in melanossomas. The hormones despite not being so clearly the role played in the melanina synthesis. But what it is clearly it is the paper of control of the mechanism of synthesis of the melanina. Classrooms of melanina Existem two main classrooms of melanina: eumelanina, of brownish or black color, and feomelanina, of colored or yellowish color.
The melanina granules if make use on the nucleus of the queratincito, in order to hinder injuries in the DNA of the cell for the rays ultraviolet. The eumelanina is much more efficient that the feomelanina in this protection, and therefore the skin cancers are more common in people of clear skin, whose relative content of eumelanina is lesser. The production of eumelanina and feomelanina is controlled for a transmembrana receiver, which if binds to the hormone melancito-stimulant, called MC1R.' ' The melanina whose main function is the pigmentao and protection against the solar radiation. It is the melanina that, for example, confers pigmentao to the skin, the eyes and the hair. In absorbing the solar radiations and hindering the ticket of these for the interior it organism, where they would have harmful effect, being therefore that the melanina elaboration increases with the exposition to the sun. However, as much the amount of melancitos as its degree of activity depends on genetic factors, what it also explains the different cutaneous coloration of the people of different etnias and the variability between proper individuals of one same etnia.