The INTEGUMENTARY System Skin Largest organ FYI About

The INTEGUMENTARY System

Skin Largest organ FYI: About six pounds on average person 3 layers

Functions of the Skin Protection Regulation of Body Temperature Reception of Stimuli Excretion Synthesis of Vitamin D Immunological Function

EPIDERMIS • • • Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale

Dermis True skin Blood vessels Nerves Hair follicles Sudoriferous glands (sweat) Sebaceous glands (oil) Ceruminous glands

Hypodermis Contains fat cells Has deep nerve endings that detect pressure Blood vessels

Sudoriferous Glands (Sweat Glands) Secrete sweat Regulates body temperature - evaporation Eliminates some waste products Two types of sweat glands: – Apocrine Glands – Eccrine Glands

Apocrine Sweat Glands FYI Skin of axilla, pubic region, pigmented areas of the body Secrete thickened sweat that promotes the growth of bacteria Active during periods of emotional stress

Eccrine Sweat Glands FYI Distributed throughout the body Secrete watery sweat to lower temp Density can be as high as 3000 per square inch in palms of the hands

Sebaceous Glands Oil glands next to hair follicles Secrete oily substance – sebum (mixture of fats, cholesterol, protein and inorganic salts) Keeps hair from drying out & becoming brittle Keeps skin soft & pliable Inhibits growth of certain bacteria

Hair (Pili) Grows from epidermis Function is protection – guards the scalp from injury and sunlight – eyebrows - eyelashes protect the eye – ears and nostrils keep out foreign objects Helps regulate body temperature Touch receptors with hair follicles

Nails Plates of tightly packed, hard, keratinized cells of the epidermis Covering over the dorsal ends of digits Provides protection Helps to grasp and manipulate small

Portions of Nails Nail Body - portion of nail visible – Free Edge - extends beyond the digits – Root - hidden in proximal nail groove – Lunula - whitish semilunar area at proximal end of the nail body Eponychium – Cuticle Nail Matrix - epithelium at proximal end – mitosis and nail growth from this area – grows at a rate of about 1 mm per week

Decubitous Ulcers Bed sores - pressure sores Lesion caused by prolonged pressure resulting in blood deficiency to a tissue overlying a bony projection Seen most frequently in individuals bedridden for prolonged periods of time

Nail Structure

Hair Color Due to amount of melanin in the cells of the hair shaft Can accumulate air bubbles in the hair shaft which causes hair to turn gray or white

Hair Structures

Know: Medulla Cortex Cuticle

Skin and Its Structures

DISORDERS/ DISEASES OF THE INTEGUMENTARY SYSTEM

Skin Cancer • • • Cancerous growths of skin tissue Often caused by prolonged exposure to the sun Three main types of skin cancers • Basal cell carcinomas • Squamous cell carcinomas • Malignant melanomas

Basal Cell Carcinomas • Tumors that arise from the basal cells of the epidermis • Slow growing - rarely metastasize • Account for over 75% of all skin cancers • Caused by chronic over-exposure to the sun • More common in fair skinned individuals over 40 years of age • Treated by excision of the tumor

Squamous Cell Carcinomas • • • Tumors that arise from the squamous cells of the epidermis Vary in the ability to metastasize Arise from pre-existing lesions on sun exposed skin More common in older, fair skinned males Treated by excision or X-Ray irradiation

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

Malignant Melanomas • • • Cancerous growths that arise from melanocytes in stratum basale Leading cause of skin cancer deaths Spreads through lymph and blood Least common type of skin cancer (3%) Caused by chronic over-exposure to UV light Treated by surgical removal of large amounts of tissue and X-Ray irradiation

Skin Cancer Risk Factors • Skin Type • light skin - greater risk • Geographic Location • higher altitude - greater risk • Age • older - greater risk • Immunological Status • immunosuppressed - greater risk • Personal Habits • occupations, leisure activities, recreation

Decubitus Ulcers • • • Bed sores/pressure sores Lesion caused by prolonged pressure resulting in blood deficiency to a tissue overlying a bony projection Seen most frequently in individuals bedridden for prolonged periods of time

Eczema • • Eczema is a skin condition of itchy and inflamed patches of skin. Greek ekzema “eruption”

Lesion • • Lesion is any abnormality in tissue, usually caused by disease or trauma. Lesion from latin “laesio”-injury

Burns • • • First Degree Burn – heat only involves the epidermis, redness as seen with sunburns. Second Degree Burn – heat penetrates the epidermis and dermis causing blisters. Third Degree Burn – heat destroys the epidermis and dermis cells appearing black, cherry-red, or ash-white. First Degree Second Degree Third Degree

Rule of 9’s

THE END!!