Chapter 5 Flashcards
accessory organs of the skin
hair, nails, and glands
integumentary system
elaborate system of distinct tissues includes glands that produce several types of secretions, nerves that transmit pulses, and blood vessels that help regulate body temperature
androgen
genetic term for an agent (usually or hormone, such as testosterone or androsterone) that stimulates development of male characteristics
ductule
very small duct
duct/o
to lead or carry
homeostasis
state of equilibrium of the internal environment of the body despite changes in external environment
-stasis
standing still
synthesize
forming a complex substance by the union of simpler compounds or elements
functions of skin
1) protect against ultraviolet rays
2) regulate body temperature
3) prevent dehydration
4) act as a reservoir for food and water
epidermis
outer layer of the skin
strata
sublayers of the epidermis
stratum corneum (location)
most superficial layer of the epidermis
basal layer (location)
deepest layer of epidermis
stratum corneum (composition)
composed of dead, flat cells with no blood supply or sensory receptors
basal layer (composition)
composed of living cells
melanocytes
located in basal layer and produces a black pigment called melanin
melanin function
provides a protective barrier from the damaging effects of the sun’s ultraviolet radiation
inheritance of melanin
melanin is genetically regulated and inherited
albino
refers to a person who cannot produce melanin and has a marked deficiency of pigment in the eyes, hair, and skin
dermis (corium)
second layer of skin that contains numerous capillaries, lymphatic vessels, nerve endings, hair follicles, and glands
product of sebaceous glands
oil
product of sudoriferous glands
sweat
subcutaneous layer (hypodermis)
binds dermis to underlying structures and is made up of loose connective tissue and adipose tissue (fat)
hypodermis (functions)
binds dermis to underlying structures, stores fat, insulates and cushions the body, and regulates temperature
exocrine glands
secrete substances through ducts to an outer surface of the body
axilae
armpits
sudoriferous glands (function)
cool the body by evaporation, excrete waste products, and moisten surface cells
sebum
oily secretion of sebaceous glands as cells disintegrate
sebum (function)
destroys harmful organisms on the skin
sebaceous glands (location)
present over the entire body except on the soles of the feet and the palms of the hands
hair (location)
found over the entire body but the lips, nipples, palms of the hands, soles of the feet, and parts of the external genitalia
hair shaft
visible part of the hair
hair root
part of hair that is embedded in the dermis
hair follicle
refers to the hair root as well as its coverings
papilla
a loop of capillaries enclosed in a covering at the bottom of the hair follicle
alopecia
baldness due to the death of papillae
nails (function)
protect the tips of the fingers and toes from bruises and injuries
nail root
where the nail is formed
nail (composition)
composed of keratinized, stratified, squamous cells
nailbed
the layer of epithelium on top of which the nail attaches and slides forward as it grows (continuous with the skin)
nail body
refers to the nail overall as it is attached to the nailbed
lunula
region on the nail body in which new growth occurs (whitish in appearance)
adip/o
fat
lip/o
fat
steat/o
fat
cutane/o
skin
hidr/o
sweat
sudor/o
sweat
ichthy/o
dry, scaly
kerat/o
horny tissue; hard; cornea
myc/o
fungus (plural, fungi)
onych/o
nail
ungu/o
nail
pil/o
hair
trich/o
hair
nid/o
nest
scler/o
hardening; sclera (white of eye)
seb/o
sebum, sebaceous
squam/o
scale
xen/o
foreign, strange
xer/o
dry
-derma
skin
py/o
pus
cry/o
cold
dermatology
the medical speciality concerned with diseases that directly affect the skin and systemic diseases that manifest their effects on the skin
dermatologist
physician who specializes in diagnosis and treatment of skin diseases
lesions
areas of tissue that have been pathologically altered by injury, wound, or infection
localized (lesion)
lesions that affect tissue over an area of definite size
systemic (lesions)
lesions that may be widely spread throughout the body
primary skin lesions
the initial reaction to pathologically altered tissue and may be flat or elevated
secondary skin lesions
changes that take place in the primary lesion as a result of infection, scratching, trauma, or various stages of a disease
flat lesions (primary)
flat, discolored, circumscribed lesions of any size
macule (flat, primary)
flat, pigmented, circumscribed area less than 1 cm in diameter; ex: freckle, flat mole, or rash that occurs in rubella
two types of elevated lesions (primary)
solid or fluid-filled
papule (solid, elevated, primary)
solid, elevated lesion less than 1 cm in diameter that may be the same color as the skin or pigmented; ex: nevus, wart, pimple, ringworm, psoriasis, eczema
nodule (solid, elevated, primary)
palpable, circumscribed lesion; larger and deeper than a papule (0.6 to 2 cm in diameter); extends into the dermal area; ex: intradermal nevus, benign or malignant tumor
tumor (solid, elevated, primary)
solid, elevated lesion larger than 2 cm in diameter that extends into the dermal and subcutaneous layers; ex: lipoma, steatoma, dermatofibroma, hemangioma
wheal (solid, elevated, primary)
elevated, firm, rounded lesion with localized skin edema (swelling) that varies in size, shape, and color; paler in the center than its surrounding edges; accompanied by itching; ex: hives, insect bites, urticaria