Chapter 4 Skin and Body Membranes Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 4 Skin and Body Membranes Diseases and Disorders

Skin Homeostatic Imbalances Athletes Foot Caused by fungal infection Itchy, red, peeling condition of the skin between the toes Nail Fungus Caused by fungal infection

Skin Homeostatic Imbalances Decubitus ulcers-bedsores Caused by restriction of blood supply resulting in cell death Slide 4.23

Skin Homeostatic Imbalances Boils and carbuncles Caused by bacterial infection Inflammation of hair follicles and sebaceous glands Common on the dorsal neck

Skin Homeostatic Imbalances Herpes- Cold sores, Fever Blisters Caused by Herpes simplex infection. Virus localized in a cutenous nerve (activated by emotional upset, fever, or UV radiation. Usually around the lips and in the oral mucosa Slide 4.23 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Skin Homeostatic Imbalances Contact Dermatitis Itching, redness, and swelling of the skin Exposure caused allergic reaction Poison ivy, nickel (jewelry), soaps

Skin Homeostatic Imbalances Impetigo Caused by bacterial infection (staphylococcus) Pink, water-filled, raised lessions Common in elementary school-aged chlfren Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Skin Homeostatic Imbalances Psoriasis Cause is unknown (Maybe autoinmune disorder) Characterized by overproduction of skin cells Triggered by trauma, infection, stress, and hormonal changes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Skin Homeostatic Imbalances Burns Tissue damage and cell death caused by intense heat, electricity, UV radiation, or chemicals Associated dangers Dehydration Electrolyte imbalance Circulatory shock (Inadequate blood circulation) Infection Can lead to a shutdown of the kidenys Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Rules of Nines Way to determine the extent of burns Body is divided into 11 areas for quick estimation Each area represents about 9% Slide 4.26 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Severity of Burns First degree burns Second degree burns Only epidermis is damaged Skin is red and swollen Second degree burns Epidermis and upper dermis are damaged Skin is red with blisters Slide 4.27 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Severity of Burns (cont.) Third-degree burns Destroys entire skin layer Burn is gray-white or black Nerve endings destroyed Skin regeneration is not possible Slide 4.27

Critical Burns Burns are considered critical if: Over 25% of body has second degree burns Over 10% of the body has third degree burns There are third degree burns of the face, hands, or feet Slide 4.28 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings