chp 4: integumentary system

what's the integumentary system composed of?

skin, glands, hair, and nails

skin

organ covering the body; made up of layers (also called cutaneous membrane)

epidermis

outer layer of skin; protects the body from the external environment

keratin

scleroprotein component of the horny, or cornified, layer of the epidermis; also the primary component of the hair and nails

melanin

dark pigment produced by melanocytes; amount present determines skin color

hair

compressed, keratinized cells that arise from hair follicles, the sacs that enclose the hair fibers

nails

horny plates made from flattened epithelial cells; found on the dorsal surface of the ends of the fingers and toes

sebaceous glands

secrete sebum (oil) into the hair follicles where the hair shafts pass through the dermis

sudoriferous glands

tiny, coiled, tubular structures that emerge through pores on the skin's surface and secrete sweat (also called sweat glands)

dermis

inner layer of skin; responsible for its flexibility and mechanical strength

hypodermis

layer between the dermis and the underlying tissues and organs; contains adipose tissue (fat), connective tissue, nerves, and blood vessels (also called subcutaneous layer)

cutane/o

skin

derm/o

skin

dermat/o

skin

hidr/o

sweat

kerat/o

horny tissue (keratin), hard

onych/o

nail

seb/o

sebum (oil)

trich/o

hair

ungu/o

nail

aden/o

gland

crypt/o

hidden

rhytid/o

wrinkles

myc/o

fungus

pachy/o

thick

scler/o

hard

staphyl/o

grapelike clusters

strept/o

twisted chains

xer/o

dry, dryness

epi-

on, upon, over

para-

beside, beyond, around, abnormal

per-

through

trans-

through, across, beyond

-a

noun suffix, no meaning

-al

pertaining to

-coccus (pl. cocci)

berry-shaped (form of bacterium)

-ectomy

excision, surgical, removal

-genic

producing, originating, causing

-ia

diseased or abnormal state, condition of

-itis

inflammation

-malacia

softening

-oma

tumor, swelling

-osis

abnormal condition (means increase when used with blood cell word roots)

-ous

pertaining to

-phagia

eating or swallowing

-plasty

surgical repair

-rrhea

flow, discharge

dermatitis

inflammation of the skin

dermatofibroma

fibrous tumor of the skin

hidradenitis

inflammation of a sweat gland

keratosis

abnormal condition (growth) of horny tissue (keratin)

onychocryptosis

abnormal condition of a hidden nail (ingrown nail)

onychomalacia

softening of the nails

onychomycosis

abnormal condition of a fungus in the nails

onychophagia

eating the nails (nail biting)

pachyderma

thickening of the skin

paronychia

diseased state around the nail (a from para is dropped)

scleroderma

hard skin (chronic hardening or induration of the connective tissue of the skin and other organs)

seborrhea

discharge of sebum (excessive)

xanthoma

yellow tumor (benign, primarily in the skin)

xeroderma

dry skin (a mild form of a cutaneous disorder characterized by keratinization and noninflammatory scaling)

abrasion

scraping away of the skin by mechanical process or injury

acne

inflammatory disease of the skin involving the sebaceous glands and hair follicles

actinic keratosis

precancerous skin condition of horny tissue formation that results from excessive exposure to sunlight; it may evolve into a squamous cell carcinoma

albinism

congenital hereditary condition characterized by partial or total lack of pigment (melanin) in the skin, hair, and eyes

basal cell carcinoma (BCC)

malignant epithelial tumor arising from the bottom layer of the epidermis called the basal layer; it seldom metastasizes, but invades local tissue and may recur in the same location; common in individuals who have had excessive sun exposure

candidiasis

infection of the skin, mouth (also called thrush), or vagina caused by the yeast-type fungus Candida albicans; Candida albicans normally present in the mucous membranes; overgrowth causes an infection; esophageal candidiasis is often seen in patients with acquired immunodeficiency syndrome (AIDS)

carbuncle

infection of the skin and subcutaneous tissue composed of a cluster of boils (furuncles) caused by staphylococcal bacteria

cellulitis

inflammation of the skin and subcutaneous tissue caused by infection; characterized by redness, pain, heat, and swelling

contusion

injury with no break in the skin, characterized by pain, swelling, and discoloration (also called a bruise)

eczema

noninfectious, inflammatory skin disease characterized by redness, blisters, scabs, and itching

fissure

slit or cracklike sore in skin

furuncle

painful skin nodule caused by staphylococcal bacteria in a hair follicle (aka a boil)

gangrene

death of tissue caused by loss of blood supply followed by bacteria invasion (a form of necrosis)

herpes

inflammatory skin disease caused by herpes virus characterized by small blisters in clusters; many types of herpes exist; herpes simplex virus type 1, for example, causes fever blisters; herpes zoster, also called shingles, is characterized by painful skin eruptions that follow nerves inflamed by the virus

impetigo

superficial skin infection characterized by pustules and caused by either staphylococci or streptococci

Kaposi sarcoma

cancerous condition starting as purple or brown papules that spreads through the skin to the lymph nodes and internal organs; frequently seen with AIDS

keloid

overgrowth of scar tissue

laceration

torn, ragged-edged wound

measles

highly contagious viral disease characterized by fever, runny nose, couch, and a spreading skin rash; it's a potentially disastrous disease which can lead to pneumonia, severe bleeding, brain infections (which may cause seizures, developmental delay or chronic brain disease), and sometimes lead to death; measles is a sig cause of death, despite the availability of a safe, effective vaccine

MRSA infection

invasion of body tissue by methicillin-resistant Staphylococcus aureus, a strain of common bacteria that's developed resistance to methicillin and other antibiotics; it can produce skin and soft tissue infections and sometimes bloodstream infections and pneumonia, which can be fatal if not treated; MRSA is quite common in hospitals and long-term care facilities but is increasingly emerging as an important infection in the general population

pediculosis

invasion into the skin and hair by lice

pilonidal cyst

abnormal pocket in the skin that contains hair and skin debris; it's frequently located near the tailbone, at the top of the cleft of the buttocks; if it becomes infected, it can be severely painful and may require surgery

pressure injury

damage of the skin and the subcutaneous tissue caused by prolonged pressure, often occurring in bedridden patients; the injury, which may be painful, can present as intact skin or an open ulcer (also called pressure ulcer and bedsore; formerly called decubitus ulcer)

psoriasis

chronic skin condition producing red lesions covered with silvery scales

rosacea

chronic disorder of the skin that produces erythema, papules, pustules, and abnormal dilation of tiny blood vessels, usually occurring on the central area of the face in people older than 30 years

scabies

skin infection caused by the itch mite, characterized by papule eruptions that are caused by the female burrowing into the outer layer of the skin and laying eggs; this condition is accompanied by severe itching

squamous cell carcinoma (SCC)

malignant growth developing from scalelike epithelial tissue of the surface layer of the epidermis; it invades local tissue and metastasize; while most commonly appearing on the skin, SCC can occur in other parts of the body including the mouth, lips, and genitals; the most frequent cause if chronic exposure to sunlight

systemic lupus erythematosus (SLE)

chronic inflammatory disease involving the skin, joints, kidneys, and nervous system; this autoimmune disease is characterized by periods of remission and exacerbations; it may also affect other organs

tinea

fungal infection of the skin; the fungi may infect keratin of the skin, hair, and nails; infections are classified by body regions such as tinea capitis (scalp), tinea corporis (body), and tinea pedis (foot); tinea in general is also called ringworm, and tinea pedis specifically is also called athlete's foot

urticaria

itchy skin eruption composed of wheals of varying sizes and shapes; uritcaria is sometimes associated with infections and with allergic reactions to food, medicine, or other agents; other causes include internal disease, physical stimuli, and genetic disorders (also called hives)

vitiligo

white patches on the skin caused by the destruction of melanocytes

type: bacterial infections

examples: carbuncle, cellulitis, furuncle, impetigo, MRSA, paronchyia

type: fungal infections

examples: candidiasis, tinea

type: parasitic infections

examples: scabies, pediculosis

type: viral infections

examples: herpes (simplex virus type 1; also called fever blister), herpes zoster (also called shingles)

dermatoplasty

surgical repair of the skin

rhytidectomy

excision of wrinkles (also called facelift)

cauterization

destruction of tissue with a hot or cold instrument, electric current, or caustic substance (also called cautery)

cryosurgery

destruction of tissue by using extreme cold, often by using liquid nitrogen