Epidermis

Outermost of the three layers that make up the skin

The epidermis is the outermost of the three major layers that constitute the skin, the inner layers being the dermis and hypodermis. The epidermal layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through transepidermal water loss. The epidermis is composed of multiple layers of flattened cells that overlie a base layer (stratum basale) composed of perpendicular columnar cells.

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