Ch 3 Flashcards
Functions of the skin
Protection from infection
Regulation of temperature
Synthesis of vitamin d
Prevention of dehydration
Excretion of waste products
Insulates body and protects from trauma through subcutaneous layer of fat
Nerve endings that provide sensory perception to the brain related to pain, heat and cold, touch, pressure, and vibration.
Main function of the skin
Protection of internal organs and the first line of defense against infection and injury
The dermis (vascular)
The thickest skin layer, composed of live cells
Contains blood vessels and lymph vessels, nerves, hair follicles, sweat glands and oil gland contains collagen and elastin
The epidermis (avascular)
The outermost protective layer of the skin. Composed of squamous epithelium and keratin. No nerves or blood supply.
Hypodermis (subcutaneous)
The bottom layer. Loose connective tissue and fat that attaches the epidermal and dermal layers to organs. Formation and storage of lipocytes for insulating and energy regulates body temperature cushions and protects
Sebaceous glands
Oil glands secrete sebum through the hair follicles distributed on the body. Their function is to lubricate the skin and hair that covers the body and it also Inhibits bacterial growth.
Sudoriferous glands
Excrete sweat which cools the body’s surface
Ceruminal gland
Produced cerumen or ear wax and protects canal from foreign body invasion.
Melanin, carotene, and hemoglobin
Combination of the 3 produce normal coloration of the skin.
Melanin-brown black pigment produced by melanocytes in the epidermis
Carotene- yellowish pigment in parts of the epidermis and dermis
Hemoglobin- pigment found in red blood cells
Radiation
Giving off of infrared heat rays to promote heat loss
Convection
Transfer of heat from skin to air
Evaporation
Returning water to air through vapor
Conduction
Transfer of heat by direct contact
Thermoreceptor
Senses heat or cold
Meissners corpuscle
Sense touch
Nociceptor
Senses pain
Pacinian corpuscle
Senses pressure
General appearance of the skin is assessed by observing
Color, temperature, texture( rough or smooth)
Moisture or dryness
Lesions and vascularity
Mobility, and condition of the hair and nails
The general appearance of the skin is assessed by palpating skin turgor possible edema elasticity
Pallor
Is an absence of or a decreased in normal skin color and vascularity and is best observed in the conjunctiva or around the mouth
Jaundice
Yellowish of the directly related to elevations in serum bilirium, and is often first observed in the sclerae and in the mucus membrane
Dark skin
Assumes a purple gray cast during inflammation
erythema
redness of the skin caused by congestion of capillaries
cyanosis
is the bluish discoloration that results from a lack of oxygen in the blood. in dark people is usually grayish
hypopigmentation
may be caused by a fungal infection, eczema, or vitiligo
hyperpigmentation
excess color can occur after sun injury or as a result of aging.
wheal
elevated mass with transient borders, no free fluid like vesicles
pustule
pus filled vesicle or bulla
nodule tumor
solid mass, deeper into the dermis than a papule
cyst
encapsulated fluid filled or semisolid mass
woods light examination
diagnoses pigmentary abnormalities detects superficial fungal and bacterial infections.
tzanck smear
secretions from a suspected lesion are examined under a microscope . multinucleated giant cells are diagnostic for herpesvirus or varicella
skin biopsy
performed to obtain tissue for microscopic examination. may be performed by scalpel excision or by skin punch instrument
