Integument

Apuntes

Integumentary system Skin is a multilayered organ that covers and protects the body The epidermis • The outer layer of epidermal cells contain keratin, which waterproofs and protects the cells and tissues that lie underneath. • The inner layers of the epidermis contains cells that continually are dividing by mitosis to replace cells that are lost or die. • Some cells in the inner layer of the epidermis provide protection from harmful ultraviolet radiation by making a pigment called melanin. Integumentary system The dermis • The dermis consists of connective tissue, nerve cells, muscle fibers, sweat glands, oil glands, and hair follicles. • Below the dermis layer is the subcutaneous layer, a layer of connective tissue that stores fat and helps the body retain heat. Integumentary system Hair and nails • Both hair and nails contain keratin and develop from epithelial cells. • Hair cells grow out of narrow cavities in the dermis called hair follicles. • Hair follicles usually have sebaceous glands associated with them that lubrivate the skin and hair. Functions of the integumentary system • Temperature regulation • Vitamin production • Protection and senses Damage to the skin Without a...