Chapter 5 Flashcards
Acne
Skin condition due to infected sebaceous glands
Albinism
Genetic disorder that affects the skin, in which there is no melanin production
Anagen
Active phase of the hair growth cycle
Apocrine sweat gland
Type of sweat gland that is associated with hair follicles in the armpits and genital regions
Arrector pili
Smooth muscle that is activated in response to external stimuli that pull on hair follicles and make the hair “stand up”
Basal cell
Type of stem cell found in the stratum basale and in the hair matrix that continually undergoes cell division, producing the kertinocytes of the epidermis
Basal Cell Carcinoma
Cancer that originates from basal cells in the epidermis of the skin
Bedsore
Sore on the skin that develops when regions of the body start necrotizing due to constant pressure and lack of blood supply; also called decubitis ulcers
Callus
Thickened area of skin that arises due to constant abrasion
Catagen
Transitional phase marking the end of the anagen phase of the hair growth cycle
Corn
Type of callus that is named for its shape and the elliptical motion of the abrasive force
Cortex
In hair, the second or middle layer of keratinocytes originating from the hair matrix, as seen in a cross-section of the hair bulb
Cuticle
In hair, the outermost layer of keratinocytes originating from the hair matrix, as seen in a cross-section of the hair bulb
Dermal papilla
(Plural = dermal papillae) extension of the papillary layer of the dermis that increases surface contact between the epidermis and dermis
Dermis
Layer of skin between the epidermis and hypodermis, composed mainly of connective tissue and containing blood vessels, hair follicles, sweat glands, and other structures
Desmosome
Structure that forms an impermeable junction between cells
Eccrine sweat gland
Type of sweat gland that is common throughout the skin surface; it produces a hypotonic sweat for thermoregulation
Eczema
Skin condition due to an allergic reaction, which resembles a rash
Elastin fibers
fibers made of the protein elastin, which resembles a rash
Eleiden
Clear protein-bound lipid found in the stratum lucidum that is derived from keratohyalin and helps to prevent water loss
Epidermis
Outermost tissue layer of the skin
Eponychium
Nail fold that meets the proximal end of the nail body, also called the cuticle
External root sheath
Outer layer of the hair follicle that is an extension of the epidermis, which encloses the hair root
First-degree burn
Superficial burn that injuries only the epidermis
Fourth-degree burn
Burn in which full thickness of the skin and underlying muscle and bone is damaged
Glassy membrane
Layer of connective tissue that surroundings the base of the hair follicle, connecting it to the dermis
Hair
Keratinous filament growing out of the epidermis
Hair bulb
Structure at the base of the hair root that surrounds the dermal papilla
Hair follicle
Cavity or sac from which hair originates
Hair matrix
Layer of basal cells from which a strand of hair grows
Hair papilla
Mass of connective tissue, blood capillaries, and nerve endings at the base of the hair follicle
Hair root
Part of hair that is below the epidermis anchored to the follicle
Hair shaft
Part of the hair that is above the epidermis but is not anchored to the follicle
Hypodermis
Connective tissue connecting the integument to the underlying bone and muscle
Hyponychium
Thickened layer of stratum corneum that lies below the free edge of the nail
Integumentary system
Skin and its accessory organs
Internal root sheath
Innermost layer of keratinocytes in the hair follicle that surround the hair root up to the hair shaft
Keloid
Type of scar that has layers raised above the skin surface
Keratin
Type of structural protein that gives skin, hair, and nails its hard, water-resistant properties
Keratinocytes
Cell that produces keratin and is the most predominant type of cell found in the epidermis
Keratohyalin
Granulated protein found in the stratum granulosum
Langerhans cell
Specialized dendritic cell found in the stratum spinosum that functions as a macrophage
Lunula
Basal part of the nail body that consists of a crescent-shaped layer of thick epithelium
Medulla
In hair, the innermost layer of keratinocytes originating from the hair matrix
Meissner corpuscle
(Also, tactile corpuscle) receptor in the skin that responds to light touch
Melanin
Pigment that determines the color of hair and skin
Melanocyte
Cell found in the stratum basale of the epidermis that produces the pigment melanin
Melanoma
Type of skin cancer that originates from the melanocytes of the skin
Melanosome
Intercellular vesicle that transfers melanin from melanocytes into keratinocytes of the epidermis
Merkel cell
Receptor cell in the stratum basale of the epidermis that responds to the sense of touch
Metastasis
Spread of cancer cells from a source to other parts of the body
Nail bed
Layer of epidermis upon which the nail body forms
Nail body
Main keratinous plate that forms the nail
Nail cuticle
Fold of epithelium that extends over the nail bed, also called the eponychium
Nail fold
Fold of epithelium that extends over the sides of the nail body, holding it in place
Nail root
Part of the nail that is lodged deep into the epidermis from which the nail grows