Human Body

Skin, Hair, and Nails

What are the various layers of the skin?

Skin is a tissue membrane that consists of layers of epithelial and connective tissues. The outer layer of the skin’s epithelial tissue is the epidermis and the inner layer of connective tissue is the dermis. The epidermis layer is replaced continually as new cells, produced in the stratum basale, mature, and are pushed to the surface by the newer cells beneath; the entire epidermis is replaced in about 27 days. The dermis, the lower layer, contains nerve endings, sweat glands, hair follicles, and blood vessels. The upper portion of the dermis has small, fingerlike projections called “papillae,” which extend into the upper layer. The patterns of ridges and grooves visible on the skin of the soles, palms, and fingertips are formed from the tops of the dermal papillae.


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