What does the epidermis do?
The primary function of the Epidermis is to act as a protective boundary with the outside environment and to reduce the risk of desiccation (drying out).
The lowest layer of the epidermis is called the germinative layer where new skin cells are constantly produced by mitosis. In this layer are specialized cells called melanocytes that produce a protein pigment called melanin when exposed to ultraviolet light (sunlight).
As the cells push upward into the middle layer of the epidermis, the layer of dying cells) the cells lose most of their water and melanin sets in the cell giving the skin color and protecting the lower layers of the skin from UV light like sunglasses protect our eyes.
The more sunlight the more melanin is produced. The more melanin the darker the skin.
The top most layer of the skin is a layer of flat squamous dead cells that forms a protective boundary with the outside world . These cells constantly peel away and are replaced from the the cells below.
Besides protection from the outside world and UV light, the epidermis holds in the moisture of the body and keeps the tissues below from desiccation or drying out.