Integumentary System Body Membranes 1 Cutaneous skin Mucosa

Integumentary System Body Membranes 1) Cutaneous (skin) & Mucosa 2) Serosa 3) Synovial

Body Membranes-Epithelial. Cutaneous (skin) & Mucosa

Epithelial & Connective. Serosa- parietal and visceral

Connective- synovial (joints)

Skin

Skin Function • Protects against: bumps, chemicals, bacteria, sun, temperature and desiccation • Aids in body heat control • Excretes urea & uric acid • Synthesizes vitamin D

Structure: Epidermis- epithelial tissue up to 5 different types of layers

Stratum basale- (bottom) • Closest to the dermis • Well fed keratinocytes • Contains melanocytes • Produce melanin that shields against sun damage

-Stratum (bottom) nd spinosum-2 -Stratum granulose-3 rd -Stratum lucidum-4 th -Stratum corneum-top 2030 layers of thick dead cells, filled with keratin

Dermis Top region = papillary layer with dermal papillae, push up epidermis = fingerprints Deeper region = reticular layer

Dermis contains blood vessels, sweat and oil glands, pressure receptors, (pacinian), rich nerve supply, hair follicles

Hypodermis: -subcutaneous, adipose tissue anchors skin

Skin color: Everyone has the same number of melanocytes, but some produce more or less melanin.

More melanin= darker skin, less melanin= lighter skin

Things that affect skin color: -Melanin- yellow, red, brown -Carotene- yellow pigment -Hemoglobin- redness -Cyanosis- blue (lack of O 2) -Pallor- pale -Jaundice- yellow, liver problems -Bruise- hematoma

Glands -All exocrine (ducts) -Sebaceous- oil, deposit sebum into a duct that opens to a hair follicle or surface -Acne: Blockage= whitehead -> blackhead -> pimple

Sudoriferous= Sweat glands (2. 5 million) • Eccrine- all over, empty at surface, temperature regulation • Apocrine- axillary and genital area, form at adolescence, empty into hair follicles. It can mix with bacteria = smell • Cerumenous- earwax (cerumen)

Hair • Fastest growing cells living in the matrix, dead cells in shaft. • Surface arrector pili muscleattaches the hair to dermis • Contracted = skin dimples

Nails- living matrix, the rest is the nonliving bed and free edge

Burns

st 1 degree- red, swollen, pain - epidermis damaged

nd 2 degree- red, pain, blister, epidermis & upper dermis

rd 3 degree- gray, white, black, no pain, entire skin, and is thick

Skin Problems: • Infection • Airway obstruction (face) • Scar tissue

• Rule of Nines: • Calculates the % burned

Neoplasms - Abnormal growths. Most are benign (not cancer)

Cancer: Basal Cell Carcinoma • From the stratum basale, can be surgically removed- curable

Squamous Cell Carcinoma • From the stratum spinosum- grows rapidly and is curable

Malignant Melanoma • From melanocytes, can be deadly • A- asymmetry • B- border irregularity • C- color • D- diameter-> 6 mm (size of an eraser on a pencil)

Other Problems

Infections • Athlete’s Foot- fungus • Boils bacterial infection • Cold Sores- Herpes S Virus • Contact dermatitis- chemical (ex: poison ivy) • Impetigo- staphylococcus

-Psoriasis- auto immune -Striae- stretch marks -Flexure lines- creases over joints -Blister- epidermis and dermis separate -Lines of Cleavage- tension lines