Anatomy_Key Terms_Ch5 Flashcards
epidermis
”"”on the skin””, a keratinized stratified squamous epithelium that contains four distinct types of cells: keratinocytes, melanocytes, tactile epithelial cells, and dendritic cells”
keratinocytes
the most abundant epidermal cell; produce keratin, a tough fibrous protein that gives the epidermis its protective properties
thick skin
covers the palms and soles; consists of five strata
stratum basale
deepest epidermal layer; also called the stratum germinativum; consists of a single row of cells, mostly stem cells representing the youngest keratinocytes; firmly attached to the underlying dermis
tactile epithelial cells
or Merkel cells; distributed sparsely among kertinocyets in the stratum basale; hemisphere-shaped; intimately associated with a disclike sensory nerve ending and functions as a receptor for touch
melanocytes
spider-shaped; make the dark skin pigment malanin
melanin
made in membrane-walled granules and then transferred through the cell processes to bnearby keratinocytes; made from an amino acid called tyrosine
stratum spinosum
several cell layers thick, second deepest layer of epidermis
dendritic cells
star-shaped cells; found in the stratum spinosum; part of the imune system; police the outer body surface using receptor-mediated endocytosis to take up foreign proteins (antigens) that have invaded the epidermis, then leave the skin and travel to a nearby lymph node and initiate an immune response to all foreign cells that carry the antigen
stratum granulosum
thin third layer of the epidermis consists of one to five layers of flattened keratinocytes, which contain abundant pre-keratin intermidiate filaments, keratohyalin granules and lamellar granules
stratum lucidum
occurs in thick skin (palms and soles) but not thin skin; consists of a few rows flat, dead keratinocytes, identical to those at the bottom of the stratum corneum
stratum corneum
”"”horny layer””; most external layer of the epidermis; many cells thick of dead keratinocytes, flat sacs completely filled with keratin because their nuclei and organellse disintegrated upon cell death”
dermis
strong, flexible connective tissue; fibroblasts, macrophages, mast cells, and scattered white blood cells; collagen, elastic, and reticular fiber types; two regions: papillary dermis and the reticular dermis
papillary dermis
superficial 20% of the dermis; areolar connective tissue containing very thin collagen and elastic fibers
dermal papillae
fingerlike projections in the papillary dermis that extend into the overlying epidermis which extend surface area for exchange of gases, nutrients, and waste products
reticular dermis
80% thickness of dermis; dense irrugalr connective tissue; extracellular matrx contains thick bundles of interlacing collagen and elastic fibers that run in many different planes (mostly parallel to the skin surface)
dermal plexus
located between the subcutaneous tissue and the dermis; nourishes the subcutaneous tissue and the structures located within the deeper portions of the dermis
subpapillary plexus
lecated just below the dermal papillae; supplies the more superficial dermal structures, the dermal papillae, and the epidermis
subcutaneous tissue
”"”below the skin””, aka hypodermis aka superficial fascia; consists of both areolar and [mostly] adipose connective tissue”
carotene
yellow-orange pigment that the body obtains from vegetable sources ie carrots & tomatoes; tends to accumulate in the stratum corneum and in the fat of the subcutaneous tissue
hematoma
general term for a clotted mass of escaped blood anywhere in the body
skin appendages
nails, hair and hair follicles, sebaceous (oil) glands, sweat glands; derive from the epithelial cells of the epidermis and extend into the dermis
nail
scalelike modification of the epdermis; built-in tools; dead, keratinized cells; hard keratine
hard keratin v soft keratin
hard keratin is toucher and more durable; the cells of hard keratin do not flake off
nail bed
nail rests on a bed of epidermis; contains only the deeper layers of the epidermis as the nail itself accounts for the topmost layer
nail matrix
actively growing part of the nail
lunule
”"”little moon””; a white crescent under the nail’s proximal region”
nail folds
lateral and proximal borders of the nail are overlapped by skin folds called
eponychium
”"”on the nail””, proximal nail fold projects onto th nail body as the cuticle or”
hair
flexible strand made of dead cells filled with hard keratin
root (hair)
part of hair embedded in the skin
shaft (hair)
part of hair that projects above the skin surface
medulla
central core of a hair; consists of large cells and air spaces (absent in fine hairs)
cortex (hair)
middle of three concentreic layers of keratinized cells of a hair; consists of several layers of flattened cells
cuticle (hair)
single layer of cells that overlap one another from below like shigles on a roof; outermost layer of a hair
hair follicles
extend from the epidermal surface into the dermis (hair)
hair bulb
the expanded, deep end of a hair follicle
hair follicle receptor
knot of sensory nerve endings wrapping around each hair bulb; aka root hair plexus
dermal papilla
nipplelike bit of the dermis that protrudes into each hair bulb; contains a know of capillaries that deliver substances that stimulate hair growth and supply nutrients to the growing hair
hair matrix
epithelial cells in the hair bulb just above the papilla
bulge (hair)
location in the superficial region of the extrenal root sheath for epidermal stem cells
arrector pili
”"”raiser of the hair””; smooth muscle cells running from the most sperficial part of the dermis to a deep-lying hair follicle”
vellus
vell=wool, fleece; body hair of women and children
terminal (har)
scalp; axillary (armpit) and pubic regions of both sexes at puberty; face, chest, arms, legs of men
male pattern baldness
most common type of true baldness; genetically determined; gender-influenced
sebaceous glands
”"”greasy””; skin’s oil glands occcur over the entire body except the palms and soles”
sebum
”"”animal fat””, secreted by the central cells in the alveoli accumulating oily lipids until they become engorged and burst apart”
holocrine secretion
holos=whole; process of sebum secretion; whole cells break up to form the product
sweat glands (sudoriferous glands)
humans have over 2.5 million distrubited over the entire skin surface, except on the nipples and parts of the external genitalia
eccrine glands
”"”secreting””; more abundant type of sweat glands, most numerous on the palms, soles, and forehead; coiled version of a simple tubular gland”
pore
the coiled, secretory base of a sweat gland lies in the deep dermis and subcutaneous tissue, and the duct runs superficially to open at the skin surface through a funnel-shaped ____
apocrine glands
mostly confined to the axillary, anal, and genital areas; larger than eccrine glands, and their ducts open into hair follicles
burn
tissue damage inflicted by heat, electricity, radiation, extreme friction, or certain harmful chemicals
first-degree burn
only the epidermis is damaged; symptoms include redness, swelling, and pain (the typical inflammatory reaction to tissue damage)
second-degree burns
injury to the epidermis and the upper part of the dermis; symptoms also include blisters
partial-thickness burns
first- and second-degree burns
third-degree burns
aka full-thickness burns, consume the entire thickness of the skin; burned area appears white, red, or blackened; worries of fluid loss and infection
basal cell carcinoma
least malignant and most common of the skin cancers; cells of the stratum basale proliferate, invading the dermis and subjutaneous tisue, and causing tissue erosions there
squamous cell carcinoma
arises from the keratinocytes of the stratum spionsum; one of the three most common types of lung cancer (25-30%), arises in the epithelium of the larger bronchi and tends to form masses that cavitate and bleed
melanoma
cancer of molanocytes, most dangerous kind of skin cancer; derived from neural crest cells, which wander widely during embryonic development which accounts for the invasive nature
dermatitis
skin inflammation
”"”on the skin””, a keratinized stratified squamous epithelium that contains four distinct types of cells: keratinocytes, melanocytes, tactile epithelial cells, and dendritic cells”
epidermis
the most abundant epidermal cell; produce keratin, a tough fibrous protein that gives the epidermis its protective properties
keratinocytes
covers the palms and soles; consists of five strata
thick skin
deepest epidermal layer; also called the stratum germinativum; consists of a single row of cells, mostly stem cells representing the youngest keratinocytes; firmly attached to the underlying dermis
stratum basale
or Merkel cells; distributed sparsely among kertinocyets in the stratum basale; hemisphere-shaped; intimately associated with a disclike sensory nerve ending and functions as a receptor for touch
tactile epithelial cells
spider-shaped; make the dark skin pigment malanin
melanocytes
made in membrane-walled granules and then transferred through the cell processes to bnearby keratinocytes; made from an amino acid called tyrosine
melanin
several cell layers thick, second deepest layer of epidermis
stratum spinosum
star-shaped cells; found in the stratum spinosum; part of the imune system; police the outer body surface using receptor-mediated endocytosis to take up foreign proteins (antigens) that have invaded the epidermis, then leave the skin and travel to a nearby lymph node and initiate an immune response to all foreign cells that carry the antigen
dendritic cells
thin third layer of the epidermis consists of one to five layers of flattened keratinocytes, which contain abundant pre-keratin intermidiate filaments, keratohyalin granules and lamellar granules
stratum granulosum
occurs in thick skin (palms and soles) but not thin skin; consists of a few rows flat, dead keratinocytes, identical to those at the bottom of the stratum corneum
stratum lucidum
”"”horny layer””; most external layer of the epidermis; many cells thick of dead keratinocytes, flat sacs completely filled with keratin because their nuclei and organellse disintegrated upon cell death”
stratum corneum
strong, flexible connective tissue; fibroblasts, macrophages, mast cells, and scattered white blood cells; collagen, elastic, and reticular fiber types; two regions: papillary dermis and the reticular dermis
dermis
superficial 20% of the dermis; areolar connective tissue containing very thin collagen and elastic fibers
papillary dermis
fingerlike projections in the papillary dermis that extend into the overlying epidermis which extend surface area for exchange of gases, nutrients, and waste products
dermal papillae
80% thickness of dermis; dense irrugalr connective tissue; extracellular matrx contains thick bundles of interlacing collagen and elastic fibers that run in many different planes (mostly parallel to the skin surface)
reticular dermis
located between the subcutaneous tissue and the dermis; nourishes the subcutaneous tissue and the structures located within the deeper portions of the dermis
dermal plexus
lecated just below the dermal papillae; supplies the more superficial dermal structures, the dermal papillae, and the epidermis
subpapillary plexus
”"”below the skin””, aka hypodermis aka superficial fascia; consists of both areolar and [mostly] adipose connective tissue”
subcutaneous tissue
yellow-orange pigment that the body obtains from vegetable sources ie carrots & tomatoes; tends to accumulate in the stratum corneum and in the fat of the subcutaneous tissue
carotene
general term for a clotted mass of escaped blood anywhere in the body
hematoma
nails, hair and hair follicles, sebaceous (oil) glands, sweat glands; derive from the epithelial cells of the epidermis and extend into the dermis
skin appendages
scalelike modification of the epdermis; built-in tools; dead, keratinized cells; hard keratine
nail
hard keratin is toucher and more durable; the cells of hard keratin do not flake off
hard keratin v soft keratin
nail rests on a bed of epidermis; contains only the deeper layers of the epidermis as the nail itself accounts for the topmost layer
nail bed
actively growing part of the nail
nail matrix
”"”little moon””; a white crescent under the nail’s proximal region”
lunule
lateral and proximal borders of the nail are overlapped by skin folds called
nail folds
”"”on the nail””, proximal nail fold projects onto th nail body as the cuticle or”
eponychium
flexible strand made of dead cells filled with hard keratin
hair
part of hair embedded in the skin
root (hair)
part of hair that projects above the skin surface
shaft (hair)
central core of a hair; consists of large cells and air spaces (absent in fine hairs)
medulla
middle of three concentreic layers of keratinized cells of a hair; consists of several layers of flattened cells
cortex (hair)
single layer of cells that overlap one another from below like shigles on a roof; outermost layer of a hair
cuticle (hair)
extend from the epidermal surface into the dermis (hair)
hair follicles
the expanded, deep end of a hair follicle
hair bulb
knot of sensory nerve endings wrapping around each hair bulb; aka root hair plexus
hair follicle receptor
nipplelike bit of the dermis that protrudes into each hair bulb; contains a know of capillaries that deliver substances that stimulate hair growth and supply nutrients to the growing hair
dermal papilla
epithelial cells in the hair bulb just above the papilla
hair matrix
location in the superficial region of the extrenal root sheath for epidermal stem cells
bulge (hair)
”"”raiser of the hair””; smooth muscle cells running from the most sperficial part of the dermis to a deep-lying hair follicle”
arrector pili
vell=wool, fleece; body hair of women and children
vellus
scalp; axillary (armpit) and pubic regions of both sexes at puberty; face, chest, arms, legs of men
terminal (har)
most common type of true baldness; genetically determined; gender-influenced
male pattern baldness
”"”greasy””; skin’s oil glands occcur over the entire body except the palms and soles”
sebaceous glands
”"”animal fat””, secreted by the central cells in the alveoli accumulating oily lipids until they become engorged and burst apart”
sebum
holos=whole; process of sebum secretion; whole cells break up to form the product
holocrine secretion
humans have over 2.5 million distrubited over the entire skin surface, except on the nipples and parts of the external genitalia
sweat glands (sudoriferous glands)
”"”secreting””; more abundant type of sweat glands, most numerous on the palms, soles, and forehead; coiled version of a simple tubular gland”
eccrine glands
the coiled, secretory base of a sweat gland lies in the deep dermis and subcutaneous tissue, and the duct runs superficially to open at the skin surface through a funnel-shaped ____
pore
mostly confined to the axillary, anal, and genital areas; larger than eccrine glands, and their ducts open into hair follicles
apocrine glands
tissue damage inflicted by heat, electricity, radiation, extreme friction, or certain harmful chemicals
burn
only the epidermis is damaged; symptoms include redness, swelling, and pain (the typical inflammatory reaction to tissue damage)
first-degree burn
injury to the epidermis and the upper part of the dermis; symptoms also include blisters
second-degree burns
first- and second-degree burns
partial-thickness burns
aka full-thickness burns, consume the entire thickness of the skin; burned area appears white, red, or blackened; worries of fluid loss and infection
third-degree burns
least malignant and most common of the skin cancers; cells of the stratum basale proliferate, invading the dermis and subjutaneous tisue, and causing tissue erosions there
basal cell carcinoma
arises from the keratinocytes of the stratum spionsum; one of the three most common types of lung cancer (25-30%), arises in the epithelium of the larger bronchi and tends to form masses that cavitate and bleed
squamous cell carcinoma
cancer of molanocytes, most dangerous kind of skin cancer; derived from neural crest cells, which wander widely during embryonic development which accounts for the invasive nature
melanoma
skin inflammation
dermatitis