Exam 2- Chapter 5 Flashcards
composed of epithelial cells, the outermost protective shield of the body, keratinized
Epidermis
Making up the bulk of the skin, tough leathery layer composed mostly of fibrous connective tissue
Dermis
Only the _____ is vascularized. Nutrients reach the ____ by diffusing through the tissue fluid from blood vessels in the dermis
dermis
epidermis
The subcutaneous tissue just deep to the skin is known as the
hypodermis
storing fat and anchors skin to underlying structures
hypodermis
the keratinoytes arise in the deepest part of the epidermis from a cell layer called the _____
stratum basal
are found in the deepest layer of the epidermis
Melanocytes
Arise from bone marrow and migrate to the epidermis
Dendritic cells
are key activators of our immune system and ingest foreign substances
Dendritic cells
a sensoy receptor for touch
Tactile cells
deepest epidermal layer; one row of actively mitotic stem cells; some newly formed cells become a part of the more superficial layers
Stratum basale
Several layers of keratinocytes unfied by desmosome. Cells contain thick bundles of intermediate filaments made of pre-keratine
Stratum spinosum
Typically 5 layers of flattened cells, organelles deteriorating; cytoplasm full of lamellar granules and keratohyaline granules
stratum granulosum
most superficial later 20-30 layers of dead cells, essentally flat membranous sacs filled with keratin
Stratum corneum
visable only in thick skin, thin translucent band
Stratum lucidum
Its cells are typical of those found in any connective tissue proper: Fibrolasts, mcrophages, and occasional mast cells
dermis
areolar connective tissue in whichfin interlacing collahen and elastic fibers from loosely woven mat that is heavily invested with small blood vessels
Papillary layer
peglike projections from the surface indent the overlying epidermis, house free nerve endings and touch receptors
dermal papillae
assumed i=to enhance grippig ability of the fingers and fet
friction ridges
is found only in the deeper layers of the epidermis
melanin
freckles and moles are local accumulations of
melanin
a yellow to orange pigments found in certain plant products
Carotene
the pinkish hue of fair skin
hemoglobin
the portion of the hair at which keratinization is complete
shaft
keratinization is still ongowing
root
central core of the hair consisting of large cells and air space
medulla
a bulky layer surrounding the medulla, consists of several layers of flattened cells
cortex
formed from a single layer of cells overlapping one another, keeps the hair from matting, provides strength
cuticle
red hair is colored by the iron containing pigment
trichosiderin
a nipple-like bit of dermal tissue protrudes into the hair bulb,containts a knot of capillaries that supplies nutrients to the growing hair and signals it to grow
hair papilla
its contraction pulls the hair follucle upright and dimples the skin surface to produce goosebumps in response to cold temperatures or fear
arrector pili
also acts as a skin lubricant and is used to scare of other animals by raising the hair
the body hair of children and alsot females is pale and fie
vellus
course long hair of eyebrows and scalp
terminal hair
excessive hairiness on a woman
hirsutism
responsible for nail growth
nail matrix
the region that like over the thick nail matrix appears as a white cresent
lunule
the proximal and lateral borders of the nail are overlapped by skin folds
nail folds
the proximal nail fold projects onto the nail body as the
cuticle
the free edge of the nail whre dirt and debris tent to accumulate and secures the free edge
hyponychium
are distributed over the entire skin surface except the nipples and parts of the external genitalia
sweat glands
far more numerous and are particularly abundant on the palms, soles of feet and forehead. Extends open at a pore
eccrine glands
regulated by the nervous system
eccrine glands
ducts empty into hair follicles
apocrine glands
releases a fatty substance and proteins so it sometimes has a milky yellowish color
apocrine
modified apocrine glands found in the lining of the external ear canal. Forms ear wax
ceruminous glands
sweat glands that secrete milk
mammary glands
simple branched alveolar glands that are found all over the body exept in the thick skin of the palms and soles
sebaceous glands, oil glands
the oily substance secreted by sebaceous glands
sebum
Biological barriers of the skin include
dendritic cells
microphages
DNA
cutaneous sensations
Temperature
touch
pain
respond to stimuli outside of the body
cutaneous sensory receptors
the least malignant and most common
basal cell carcinoma
the second most common skin cancer, arises from the keratinocytes of the stratum spinosum
squamous cell carcinoma
the lesion appears as a scaly reddened papule, arise most often on the head
squamous cell carcinoma
the most dangerous skin cancer because it is highly metastatic and resistant to chemotherapy
Melanoma
ABCD rule for melanoma
Asymmetry
Border irregularity
Color
Diamerter
in this burn only the epidermis is damaged
first degree
injure the epidermis and the upper region of the dermis, blisters also appear
Second degree burn
full thickness burn involving all regions of the skin
third degree burn