Concept in Definition ABC

The Epidermis is the most layer superficial of the skin and as its name indicates it is located above the dermis.

The epidermis is the superficial lining of the body, practically covering it in its whole, except for the orifices and mucous membranes where it continues with a lining tissue called epithelium.

From a microscopic point of view, it is made up of flattened cells that are arranged in the form of layers, of which two can be distinguished mainly, an inner or deep layer made up of active cells in constant replication and an outer layer made up of cells dead. The cells multiply in the deepest layer of the epidermis and from there they pass to more superficial layers, as the cells reach the exterior they leave filling with keratin until the most superficial layer or stratum corneum consists only of cells without organelles in which all the space is occupied only by keratin. In this process of transformation the unions between the cells are weakened which favors their detachment, shedding and giving way to new cells from the deeper layers.

The epidermis has thickness variations depending on its location, at the level of the palm of the hands and the soles of the feet reach their maximum dimensions to allow greater protection of these areas, in areas such as around the eyes it is less thick.

The epidermis lacks blood vessels, but is rich in nerve endings which gives it great sensitivity. In its deepest layer are cells called melanocytes whose function is to produce a pigment called Melanin which gives the skin its color. Melanin is produced in response to exposition to sunlight, especially ultraviolet radiation, its function is to act as a barrier that does not allow the passage of these radiations to the skin, with greater exposure to sunlight there will be a higher production of melanin which will produce a pigmentation or darkening of the skin.

In the disease known as Albinism there is a congenital defect that leads to melanin not being produced so the skin, hair and iris of the eyes are very light in color, it is also immune-mediated destruction of melanocytes may occur leading to depigmentation of the skin resulting in the known disorder What Vitiligo.