Integumentary System

Skin consists of the epidermis (keratinized stratified squamous epithelium) and the dermis (dense irregular connective tissue). Cells of the epidermis include keratinocytes, melanocytes, langherhan’s cells, and merkel’s cells. Epidermal derivatives include hair follicles and hair, sweat (sudoriferous) glands, sebaceous glands, nails, and mammary glands.

Attachment of the epidermis and the dermis is enhanced by increased interface between them. They are represented by fingerlike protrusions called dermal papillae that project into the undersurface of the epidermis. Papillae are complemented by epidermal ridges or rete ridges/pegs (which appear to project into the dermis). The dermis contains two layers: