chapter 16 Flashcards
integumentary
system
The skin and its accessory structures (hair, nails, and glands)
sebaceous glands and the sweat glands
produce sebum, an oily secretion, and sweat glands produce sweat, a watery secretion.
Epidermis
a thin, cellular membrane layer; containing keratin
Dermis
dense, fibrous, connective tissue layer; containing collagen
Subcutaneous layer
—thick, fat-containing tissue
squamous
epithelium
. Epithelium is the covering of both the internal and the external surfaces of
the body. Squamous epithelial cells are flat and scale-like. In the outer layer of the skin,
these cells are arranged in several layers (strata) to form stratified squamous epithelium.
basal layer
s the multilayered cells of the epidermis. The deepest layer is
called the basal layer [4]. T
stratum corneum
. In their movement toward the most superficial layer of the
epidermis, called the stratum corneum [5], the cells flatten, shrink, lose their nuclei, and
die, becoming filled with a hard protein material called keratin.
melanocytes
The basal layer of the epidermis contains special cells called melanocytes [6]. Melanocytes
contain a pigment called melanin that is transferred to other epidermal cells and gives
color to the skin.
albinos
Individuals who are incapable of forming melanin are called
albinos. Skin and hair are white
Eumelanin (eu- = true) is more common and is a brown-black pigment. Pheomelanin (pheo- = dusky) is a red-yellow
pigment. People with darker skin have more eumelanin, whereas people with lighter skin have more pheomelanin.
Pheomelanin doesn’t protect the skin from damaging ultraviolet rays and makes lighter-skinned people, and especially
redheads, more susceptible to skin cancer
elastin
(protein that is elastic and helps skin to
return to its original position when pinched or poked)
Collagen (colla
= glue)
) is a fibrous protein material found in bone, cartilage, tendons, and ligaments, as
well as in the skin. It is tough and resistant but also flexible
A hair fiber is composed of a tightly fused meshwork of cells filled with the hard protein
called keratin
produce keratinized cells that move upward
through hair follicles (sacs within which each hair fiber grows)
lunula
placed completely.
The lunula is a semilunar (half-moon–shaped) whitish region at the base of the nail
plate.
cuticle
a narrow band of epidermis (layer of keratin), is at
the base and sides of the nail plate
paronychium
is the soft tissue surrounding the
nail border. Figure 16-3A illustrates the anatomic structure of a nail.
Onycholysis
(onych/o = nail) is the
loosening of the nail plate with separation from the nail bed
eccrine sweat glands
Sweat glands (the most common type are eccrine sweat glands) are tiny, coiled glands found on almost all body surfaces (about 2 million in the body).
apocrine sweat glands
A special variety of sweat gland, active only from puberty onward and larger than the
ordinary kind, is concentrated in a few areas of the body near the reproductive organs and
in the armpits. These glands (apocrine sweat glands) secrete an odorless sweat, containing
substances easily broken down by bacteria on the skin. The bacterial waste products
produce a characteristic human body odor. The milk-producing mammary gland is another
type of apocrine gland; it secretes milk after the birth of a child.
albin/o
white
caus/o
burn, burning
cauter/o
heat, burn
electrocautery
An instrument containing a needle or blade used during surgery
to burn through tissue by means of an electrical current.
Electrocauterization is very effective in minimizing blood loss.
diaphor/o
profuse sweating
see hidr/o
erythem/o,
erythemat/o
redness
erythema
Flushing; widespread redness of the skin. Pronunciation is
ĕr-ĭ-THĒ-mă. Erythematous means pertaining to erythema
hidr/o
sweat
ichthy/o
dry, scaly
fish-like
anthrac/o
black (as coal)
chlor/o
green
cirrh/o
tawny yellow
cyan/o
blue
lute/o
yellow
poli/o
gray
xanth/o
yellow
kerat/o
hard
myc/o
fungus (fungi
include yeasts,
molds, and
mushrooms)
onych/o
nail (see ungu/o
phyt/o
plant
pil/o
hair (see trich/o),
hair follicle
rhytid/o
wrinkle
seb/o
sebum (oily
secretion from
sebaceous glands)
squam/o
scale-like
trich/o
hair
ungu/o
nail
xanthoma
Nodules develop under the skin owing to excess lipid deposits and
can be associated with a high cholesterol level. A xanthoma that
appears on the eyelids is a xanthelasma (-elasma = a flat plate)
xer/o
dry
xerosis
This is very dry skin.
crust
Collection of dried serum and cellular debris
cyst
Thick-walled, closed sac or pouch containing fluid or semisolid material.
erosion
Wearing away or loss of epidermis
fissure
Groove or crack-like sore.
macule
Flat, pigmented lesion measuring less than 1 cm in diameter
nodule
Solid, round or oval elevated lesion 1 cm or more in diameter.
papule
Small (less than 1 cm in diameter), solid elevation of the skin.
polyp
Growth extending from the surface of mucous membrane
pustule
Papule containing pus
ulcer
Open sore on the skin or mucous membranes (deeper than an erosion).
vesicle
Small collection (papule) of clear fluid (serum); blister
wheal
Smooth, edematous (swollen) papule or plaque that is centrally redder
or paler than the surrounding skin.
alopecia
Absence of hair from areas where it normally grows
ecchymosis (plural:
ecchymoses)
Bluish-purplish mark (bruise) on the skin.
Ecchymoses (ec- = out, chym/o = pour) are caused by hemorrhages into the skin
from injury or spontaneous leaking of blood from vessels
petechia (plural: petechiae)
Small, pinpoint hemorrhage.
pruritus
Itching
acne
Chronic papular and pustular eruption of the skin with increased
production of sebum.
cellulitis
Diffuse, acute infection of the skin marked by local heat, redness, pain,
and swelling.
eczema (atopic dermatitis)
Inflammatory skin disease with erythematous, papulovesicular, or
papalosquamous lesions.
exanthematous viral diseases
Rash (exanthem) of the skin due to a viral infection
gangrene
Death of tissue associated with loss of blood supply.
impetigo
Bacterial inflammatory skin disease characterized by vesicles, pustules,
and crusted-over lesions.
psoriasis
Chronic, recurrent dermatosis marked by itchy, scaly, red plaques
covered by silvery gray scales
scabies
Contagious, parasitic infection of the skin with intense pruritus
(Figure 16-15B).
scleroderma
Chronic progressive disease of the skin and internal organs with
hardening and shrinking of connective tissue
systemic lupus
erythematosus (SLE)
Chronic autoimmune inflammatory disease of collagen in skin, joints,
and internal organs
tinea
Infection of the skin caused by a fungus.
urticaria (hives)
Acute allergic reaction in which red, round wheals develop on the skin
vitiligo
Loss of pigment (depigmentation) in areas of the skin (milk-white
patches)
callus
Increased growth of cells in the keratin layer of the epidermis caused
by pressure or friction.
keloid
Excess hypertrophied, thickened scar developing after trauma or
surgical incision.
keratosis
Thickened and rough lesion of the epidermis; associated with aging or
skin damage.
leukoplakia
White, thickened patches on mucous membrane tissue of the tongue or cheek (evolves to squamous cell carcinoma)
nevus (plural: nevi)
Pigmented lesion of the skin
verruca (plural: verrucae)
Epidermal growth (wart) caused by a virus
basal cell carcinoma
Malignant tumor of the basal cell layer of the epidermis
squamous cell carcinoma
Malignant tumor of the squamous epithelial cells in the epidermis.
malignant melanoma
Cancerous growth composed of melanocytes
Kaposi sarcoma
Malignant, vascular, neoplastic growth characterized by cutaneous
nodules
curettage
Use of a sharp dermal curette to scrape away a skin lesion.
electrodesiccation
Tissue is destroyed by burning with an electric spark.
Mohs surgery
Thin layers of malignant tissue are removed, and each slice is
examined microscopically to check for adequate extent of the resection
ABCDE
asymmetry (of shape), border (irregularity), color (variation within one lesion), diameter (greater than 6 mm), evolution (change)—characteristics associated with melanoma
