1. The Skin

2.  Two layers:  Epidermis  Dermis

3.  A stratified squamous epithelium (many layers of flat cells)  Cells rapidly divide at base of epidermis to replenish the cells worn away at the top  Fills with fibrous keratin and release a waterproofing glycolipid, and eventually die  Continuous process means we get new skin every few weeks

4.  Consists of a fairly dense connective tissue with many resilient elastic fibers and strong collagen fibers  Contains:  Hair follicles  Oil and sweat glands  Muscles  Nerves  Sensory receptors  Blood vessels

5.  Beneath the skin  Layer a of adipose tissue

6.  Metabolic function  Vitamin D  Calcium  Homeostasis  Temperature Regulation  Waterproofing  Protection from microbes  Sensory reception of environment  Pain  Temperature