epidermis
Last reviewed 01/2018
The epidermis is the most superficial layer of the skin. It is a stratified squamous epithelium. More deeply, it joins with the dermis at the dermo-epidermal junction. It varies in thickness from approximately 0.1mm in eyelids to 1mm in the plantar surface of the foot.
Loss of cells superficially is countered by continual cell production within the stratum basale, the deepest of the five skin layers which are - superficially to deep:
- stratum corneum
- stratum lucidum
- stratum granulosum
- stratum spinosum
- stratum basale
An alternative classification has the basal layer deepest, the prickle or granular layers above this, and the horny layer most superficially.
Hairs and nails are both types of appendage which emerge from the epidermis. Sweat glands and sebaceous glands both pass through the epidermis.