The INTEGUMENTARY System Support Systems Unit 2

Functions of the Skin Protection Vitamin D Production Sensory Organ Temperature Regulation Protection against UV Light

Layers of the Skin Epidermis Dermis Subcutaneous

Epidermis Outer layer of skin Avascular - no blood vessels

Dermis Layer of skin under the epidermis Contains the blood vessels, glands, hair follicles, and nerve endings of the skin

Subcutaneous Layer Composed of fat that helps insulate the body from heat and cold, provides protective padding, and serves as an energy storage area Also called the hypodermis

Nails Composed of dead (keratinized) skin cells Helps to grasp and manipulate small objects

Glands of the Skin Sudoriferous Glands (Sweat Glands) Sebaceous Glands (Oil Glands)

Sudoriferous Glands (Sweat Glands) Primary function - regulates body temperature by evaporation of water

Sebaceous Glands Oil glands usually associated with hair follicles Secrete an oily substance called sebum a mixture of fats, cholesterol, protein and inorganic salts Keeps hair from drying out and becoming brittle

Hair Composed of dead (keratinized) skin cells Primary function is protection guards the scalp from injury and sunlight eyebrows - eyelashes protect the eye ears and nostrils keep out foreign objects

Hair Structures

Diseases and Disorders Integumentary System

Acne An inflammation of the sebaceous glands and hair follicles Primarily affects teenagers due to increased hormonal activity which causes the sebaceous glands to be over-active Treated with topical creams that dry out the skin and oral antibiotics that decrease the inflammation of the sebaceous glands

Athletes Foot A common infection caused by the tinea fungus Symptoms include itching, burning, and cracked, scaly skin between the toes and on the feet It grows best in damp, dark, warm places Treatment includes over-the-counter antifungal creams for most cases and prescription medicines for more serious infections.

Ring Worm Caused by tinea fungus Causes a red skin rash that forms a ring on normal looking skin This is not caused by a worm Common treatment includes over-the-counter antifungal creams

Jock Itch Cause by the tinea fungus Causes an itchy, burning rash in the groin area Common treatment includes over-the-counter- antifungal creams

Skin Cancer Uncontrolled growth of cells The sun is responsible for over 90% of all skin cancers There are 3 most common forms of skin cancer:

Basal Cell Carcinoma The most common form of cancer 1 million new cases estimated in the U.S. each year Occurs most frequently on the sun-exposed areas of the body (face, ears, neck, scalp, shoulders, and back)

Squamous Cell Carcinoma The second most common form of skin cancer Over 250,000 new cases per year Most cases are caused by chronic overexposure to the sun Tumors apperar most frequently on the sun exposed face, neck, bald scalp, ears, and lips

Melanoma Arises from the melanocytes The least common but most dangerous form of skin cancer In men is most common on the trunk, head, and neck. In women is most common on the lower legs

ABCDE Method to Assess Skin Cancer A - Asymmetry B - Border C - Color D - Diameter E – Evolution or Elevation