The skin is the largest organ of the body and has three main layers - the epidermis, dermis and subcutaneous layer. The epidermis is the outer layer and does not contain blood vessels, while the dermis below contains connective tissue and collagen. The deepest subcutaneous layer contains fat cells. The skin also contains sweat glands, hair follicles, nails and oil glands, and acts as a protective barrier while also sensing touch and temperature. Skin can be affected by pathogens, diseases, infections and cancers.

1. Integumentary System Anatomy and Physiology

2. System Includes Sweat glands Oil Glands Hair Nail Layers of skin Cutaneous membranes Skin pathogens Sensory receptors

3. The Skin The skin is the largest organ on or in the body Protects the body from foreign agents and germs Can sense temperature, pain, touch, and pressure The skin secrete fluids through the sweat glands and sebaceous The skin has three main layers

4. Three layers of skin Skin Epidermis (the outer membrane Layer) Dermis ( the middle layer) Subcutaneous (the deepest layer)

5. Epidermis Has stratified squamous epithelium, that consist of scale-like cells Does not have a blood supply or connective tissues Depends on nourishment from the deeper layers of skin Contains two cells called Keratin and Melanocytes The basal layer is the deepest layer within the epidermis

6. Deeper layers Dermis Compose of connective tissues Compose of collagen fibers Subcutaneous House cells called lipocytes Act as an insulation for heat and cold Contains fatty tissues

7. Accessory Organs Hair Nails Sweat Glands Sebaceous

8. Hair Hair Shaft Grows toward the Skin surface Follicle Hair root force older keratin Cells to move upward

9. Nails Nail body is the flat-plate keratin that covers the ends of fingers and toes, or nail bed Nail root is the base of the nail and protected by the cuticle The free edge is the edge of the nails Lunula is the half-circle area at the base of the nail

10. Sweat Glands Sudoriferous glands are found throughout the body, and found in the dermis Sweat duct is the surface of the skin Sweat pore is the opening of the skin

11. Skin Pathogens Skin lesions Skin discolorations Skin diseases Skin cancers Burns or infections Skin viruses

12. Diagnostic Procedures Clinical Laboratory Tests Culture and sensitivity

13. Therapeutic Procedures Skin Grafting Surgical procedures Plastic surgery procedures

14. The End