AP1 chapter 6
thick skin
-palms of hands, soles of feet -no hair follicles or sebaceous glands -stratum lucidum present
three main variations in the epidermis
-thickness -colorations -skin markings
where does the process of kerantinization begin
a layer in the epidermis called the stratum granulosum
an open comedo
blackhead
in the first step of wound healing, cut blood vessels release ______ into the wound
blood
location of mammary glands
breats
the cells of stratum corneum contain large amounts of the protein....
keratin
what lubricates the epidermis and hair helps make the integument water resistant
sebum
aprocrine sweat glands are classified as _______ glands
simple, coiled, tubular
also called stratum germinativum due to mitosis
stratum basale
waterproof protective covering composed of sebum and sloughed off cells
vernix caseosa
stimuli detected by sensory receptors of the skin
-cold -vibration -pressure
normal skin color results from a combination of colors of .....
-hemoglobin -melanin -carotene
3 cell types found in stratum basale
-keratinocytes -melanocytes -merkel cells
skin cells types
-keratinocytes -melanocytes -merkel cells -dendritic cells
overall, keratinocytes are present for about ______ fllowing their formation
1 month
main functions of the subcutaneous layer
acts as an energy reservoir protects the body provides thermal insulation
recessive condition; nonfunctional enzyme for melanin production characterized by white hair, pale skin, pink irises
albinism
location of sebaceous glands
associated with hair follicles over much of the skin
the net effect of vasoconstriction of the dermal blood vessels is a shunting of blood _______ from the periphery of the body to ________ heat
away conserve
location of apocrine glands
axillary, anal areolar, and pubic regions
components of the dermis (7)
blood vessels sweat glands sebaceous glands hair follicles nail roots sensory nerve endings smooth muscle tissue
overexposure to UV rays is the primary factor in the development of almost all skins _______
cancers
plays a role in vitamin a production and normal vision as well as improved immunity
carotene
keratinocytes in the epidermis produce __________ when exposed to UV radiation
cholecalciferol
lines of cleavage in the skin relate to the predominant orientation of ______ fiber bundles
collagen
the predominant type of protein fiber found in the dermis is...
collagen
when the skin is stretched beyond its capacity some ______ fibers are torn and result in stretch marks, which are called ______
collagen striae
stratum corneum living or dead
dead - corneum
stratum lucidum living or dead
dead - lucidum
stratum basal is the ...
deepest layer
Because an entire portion of skin has been lost, and water cannot be retained in the area, a major concern with third degree burns is ______.
dehydration
the two layers of integument
dermis and epidermis subcutaneous layer- hypodermis (Not part of skin)
location of merocrine glands
distributed throughout the body
an intermediate product in the process of keratin maturation
eleidin
the kerantinocytes within the stratum lucidum are flattened and filled with the protein _________
eleidin
kerantinized stratified simple squamous
epidermis
location of ceruminous glands
external acoustic meatus
cerumen, together with tiny hairs on the ear canal, helps trap __________ and _____________ keeps them from reaching the eardrum
foreign particles small insects
________ is an area of excessive melanocyte activity
freckle
located on the fingers, palms, soles, and toes are formed from large folds and valleys on both the dermis and the epidermis
friction ridges
-scattered among k'cytes -produce and store pigment in response to UV light
melanocytes
the ultraviolet rays in sunlight are prevented from penetrating to the deeper dermis layer by specialized cells called...
melanocytes
tactile cells are also called
merkel cells
the most numerous and widely distributed sweat glands in the body are
merocrine sweat glands
layer of embryonic cells that develop into the dermis
mesenchyme
nevus
mole
________ is caused by an increase in melanocyte numbers
nevus
similar to a pustule, but extending into the deeper skin layers
nodule
skin color
normal color due to hemoglobin, melanin, carotene
layers of cells covering the development embryonic epithelium _______
periderm
which layer of the dermis of the skin forms the deeper, major portion of the dermis and extends from the papillary layer to the underlying subcutaneous layer?
reticular layer
sebaceous glands are activated primarily by ___________ during puberty in both sexes
sex horomones
integument
skin
integumentary system contains
skin, hair, nails sweats glands, and sebaceous glands
As an individual ages the skin repair processes takes longer to complete because of the reduced number and activity of ------ cells
stem
as an individual ages, the skin repair process takes longer to complete because of the reduced number and activity of _____ cells
stem
as a result of the ageing process hair follicles can actually _______ production of hairs
stop
attached to basement membrane
stratum basale
deepest layer of epidermis
stratum basale
deepest layer of the epidermis
stratum basale
the two types of general exocrine glands
sweat glands sebaceous glands
what stimulates production of melanin
uv light
if the body is too warm the dermal blood vessels _____ so more blood can travel _______ to the surface and excess can be lost
vasodilate close
-dermal blood vessels increase in diameter -so more blood can travel through them
vasodilation
the skin is described as
waterproof
reticular means "network" and refers to the
weblike meshwork of collagen fibers
a closed comedo
whitehead
what contains the capillaries that supply nutrients to the cells of the epidermis?
dermal papillae
nerve fibers in the skin monitor sensory receptors in the.....
dermis and epidermis
the major functions of merocrine sweat glands are
secretion protection thermoregulation
epidermal dendritic cells are found in what parts of the strata?
spinosum granulosum
- hornlike layer - most superficial layer - has 20-30 layers of dead, interlocking keratinized cells
stratum corneum
-has 2-5 layers of k'cytes -granular layer -where kerantinization begins
stratum granulosum
- has 2-3 cell layers - clear layer - found only in thick skin
stratum lucidum
in thick skin, the layers of the epidermis that contain dead keratinocytes are the.....
stratum lucidum and stratum corneum
nondividing k'cytes attached to desmosomes
stratum spinosum
epidermal dendritic cells are found in
stratum spinosum and stratum granulosum
the ________ of the integument has immune cells
stratum spinosum/dermis
drugs are often injected into the...
subcutaneous layer
skin cancer can develop in people of any age T/F
true
the _____ and _______ together secrete and absorb materials and play a role in immunity
dermis epidermis
friction ridges assume the shapes of complex arches and whorls in the .....
thick skin
stratum basale living or dead
living - basale
stratum granulosum living or dead
living - granulosum
stratum spinosum living or dead
living - spinosum
as an individual ages skin repair processes takes ________
longer
migration of keratinocytes from the stratum basale to the stratum corneum takes about ________
2 weeks
the dead, keratinized cells usually remain in the exposed corneum layer for an additional ______
2 weeks
how many layers of kerantinocytes comprise the stratum granulosum
3-5
ceruminous glands are modified sweat glands located only in the
External acoustic meatus
-bright red color when oxygenated -seen most easily in fair skin -more visible if blood vessels dilate
hemoglobin
sabaceous glands are classified as __________ glands that discharge an oily, waxy secretion called _________
holocrine gland sebum
largest organ, contains all 4 tissue types, protects internal structures
integument
Why are drugs often injected into the subcutaneous layer?
its extensive vascular network promotes rapid absorption
skin cell types (4)
kerantinocytes melanocytes merkel cells dendritic cells
-protein that strengthens epidermis -makes skin almost waterproof
keratin
-most abundant cells in epidermis -found in all layers -divide to generate new cells -old cells shed at surface
keratinocytes
melanin is transferred to..
keratinocytes
mammary glands only become functional in which of the following conditions
lactating females pregnant females