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acne vulgaris
a common inflammatory skin reaction caused by bacteria, dead skin cells, or dried sebum that clogs hair follicles and prevents sebum from passing up through the pores
swelling of the face, lips, throat, or airways
apocrine gland
correlates with the hair follicles present in the perineum, axillae, and areolae of the breasts
arrector pili muscle
triggers hair follicle on the body to flex causing the hair to rise up
basal cell carcinoma
the most common skin cancer that is generally found on the head or neck; it may be serious but is not usually fatal
flesh-colored, small bump with a dark center
large blister
bullous impetigo
type of impetigo that has large, flaccid bullae on the skin that rupture and leave a thin brown crust
skin abscess that connects to others below the surface of the skin to form clusters, often forming when one of more hair follicles become infected
localized infection and inflammation of the skin and tissues that are immediately beneath the skin
comedone extraction
use of a comedone extractor by a healthcare professional to remove blackheads and whiteheads by incising the pore and then using gentle pressure around the pore opening with a wire loop
cystic acne
lesions that are usually large, red, painful, and pus-filled nodules that merge under the skin and often leave scars
has antimicrobial and/or cytotoxic properties and is part of the body’s first immune defense
dermatosis papulose nigra
small dark or skin-colored bumps on the face, neck, and upper torso, common in people with darker skin colors
the layer of skin below the epidermis connected to the epidermis by dermal papillae
disseminated zoster
herpes zoster rash that affects three or more dermatomes
eccrine gland
is located over the skin entirely, secretes sweat, and aids in thermoregulation
(deep impetigo) a skin infection that occurs deep inside the skin characterized by shallow, small ulcers that look punched-out and may contain pus
(atopic dermatitis) rash characterized by itchy, chronic inflammation of the upper skin layers and is associated with a heightened immune response
ingredient that soothes skin dryness
a change in skin color due to a change in blood flow
filiform wart
long, small, narrow growth that appears on the lips, face, or eyelids
flat wart
may appear in areas that are shaved or along stretch marks
an infection of the skin follicle
genital wart
(condyloma acuminata, venereal wart) occurs on the vagina, vulva, cervix, or penis
herpes simplex
viral infection that can cause painful blisters or ulcers
herpes zoster
(shingles) maculopapular rash associated with shingles most often appears on the trunk of the body along a thoracic dermatome
the chemical process in which a hydroxyl group (–OH) is introduced into an organic compound
darkened patches of skin (liver spots)
the subcutaneous fatty layer beneath the dermis that anchors the dermis to the underlying tissues of the body
lighter patches of skin (age spots)
highly contagious bacterial skin infection that forms pustules and yellow crusty sores
Kaposi sarcoma
a rare type of cancer caused by a virus
a thick fibrous scar caused by excessive collagen formation in response to trauma or a surgical incision
fibrous water-repellant protein gives the epidermis its strong, protective quality
a thickening of plasma membranes of a cell
cell that produces keratin
Langerhans cell
antigen-processing cell that determines the appropriate response to (inflammation) or tolerance of foreign substances
the softening of tissues caused by prolonged wetting or soaking
malignant melanoma
the most dangerous type of skin cancer; originates in the melanocytes
dark brown to black pigment protects the keratinocytes and nerve endings from ultraviolet light damage that appears in the skin and hair
cell that produces melanin and keratinocyte
Merkel cell
found in the stratum basale and serves as a sensory receptor for light touch
mitotic activity
the degree in which a population of cells proliferates
MOHS procedure
layers of the skin are removed and examined for cancer cells until no signs of cancer remain
mosaic wart
wart that grows in clusters
nonbullous impetigo
type of impetigo that has pustules that rapidly break down and form thick, adherent, honey-colored crusts on the face and extremities
bone demineralization
palmar wart
wart on the palm of the hand
papillary layer
thin, dermal layer of the dermis composed of loose connective tissue, which contacts the epidermis
lice infestation
pediculosis capitis
lice infestation of the scalp
pediculosis corporis
lice infestation of the body
pediculosis pubis
lice infestation of the hairs of the anal and genital areas but can also infest the thigh, chest, and facial hair
(sweat) excess water and salts that are eliminated from the body via sweat glands
photodynamic therapy
using lasers and chemicals on the skin
has a small area of red skin and can be painful or cause discomfort
any of various skin conditions characterized by dry scaling patches of skin
plantar wart
wart on the sole of the foot
postinflammatory hyperpigmentation
temporary pigmentation that occurs after an injury or inflammatory skin condition, most commonly seen in people with darker skin types
prodromal state
period between the appearance of initial symptoms and the full development of an illness causing headache, malaise, chills, or photophobia
a recurring, chronic skin condition that causes one or more raised areas of red skin patches with silvery scales and a distinct border
similar to a pimple but contains white or yellow pus
Raynaud phenomenon
a condition that causes pale or blue fingers with cold exposure
reticular layer
thick, dermal layer of the dermis that consists of dense connective tissue, collagen bundles, and houses most of the sweat glands, sebaceous glands, hair follicles, hair, muscles, blood vessels, and deep sensory neurons
tissue that produces red and white blood cells and platelets; where hematopoiesis takes place
sebaceous gland
secretes sebum, an oily substance that makes the hair and skin waterproof
seborrheic dermatitis
inflammatory skin reaction primarily on the scalp and face
squamous cell carcinoma
the second most common type of skin cancer that generally develops on sun-exposed areas but can grow where sun exposure is limited
stratum basale
(stratum germinativum) deepest layer of the epidermis that contains melanocytes and keratinocytes
stratum corneum
thickest and outermost layer of the epidermis that secretes defensins as part of the body’s first immune defense
stratum granulosum
layer above the stratum spinosum that contains a glycolipid, which slows water loss across the epidermis
stratum lucidum
layer of skin only found in thick areas like the soles of the feet and palms of hands
stratum spinosum
layer above the stratum basale and contains cytoplasmic processes (spines) that extend outward and contact neighboring cells
subcutaneous tissue
the subcutaneous fatty layer (hypodermis) beneath the dermis that separates the skin from the underlying tissue
systemic lupus erythematosus (SLE)
a chronic autoimmune inflammatory disorder involving connective tissues of the joints, skin, kidneys, mucous membranes, and blood vessel walls
red marks on the skin caused by the widening of shallow blood vessels
the skin does not snap back when pinched; instead, it maintains a tentlike shape, which may indicate dehydration
(ringworm) may be found on the feet, beard, body, groin, scalp, or toes
tinea barbae
(beard ringworm) fungal infection of the beard
tinea capitis
fungal infection of the scalp
tinea corporis
fungal skin infection of the arms, trunk, legs, and face
tinea cruris
fungal infection of the groin
tinea pedis
(athlete’s foot) fungal infection of the feet
tinea unguium
(onychomycosis) fungal infection of the toenail or fingernail
transdermal administration
placed on the skin and absorbed either locally or systemically
(hives) rash of raised, swollen, flesh-colored or red bumps or welts on the skin
(chickenpox) caused by the varicella-zoster virus
(wart) raised or flat growth caused by the viral infection human papillomavirus
small blister
chronic autoimmune disorder that causes partial or total loss of skin color in patches
flesh-colored small bump that does not have a dark center
skin dryness

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