which epidermal cell type is most nymerous
a.)keratinocyte
b.)melanocyte
c.)dendritic cell
d.)tactile cell
keratinocyte
Which cell functions as part of the immune system
a.)keratinocyte
b.)melanocyte
c.)dendritic cell
d.)tactile cell
dendritic cell
the epidermis proves a physical barrier due largely to the presence of
a.)melanin
b.)carotene
c.)collagen
d.)keratin
keratin
skin color is determined by
a.)the amount of blood
b.)pigments
c.)oxygenation level of the blood
d.)all of the above
all of the above
the sensations of touch and pressure are picked up by receptors.
a.)the stratum spinosum
b.)the dermis
c.)the hypdermis
d.)stratum corneum
the dermis
which is not a true statement about the papillary layer of the dermis?
a.)it is largely areolar connective tissue
b.)it is most responsible for the toughness of the skin
c.)it contains nerve endings that respond to stimuli
d.)it is highly vascular
it is most responsible for the toughness of the skin
skin surface markings that reflect points of tight dermal attachment to underlying tissues are called.
a.)tension lines
b.)papillary ridges
c.)flexure lines
d.)dermal papillae
flexure lines
which of the following is not an epidermal derivative?
a.)hair
b.)sweat gland
c.)sensory receptor
d.)sebaceous gland
sensory receptor
an arrector pili muscle
a.)is associated with each sweat gland
b.)can cause a hair to stand up straight
c.)enables each hair to be stretched when wet
d.)provides new cells for continued growth of its associated hair.
can cause a hair to stand up straight
the product of this type of sweat gland includes protein and lipid substances that become odoriferous as result of bacterial action:
a.)apocrine gland
b.)eccrine gland
c.)sebaceous gland
d.)pancreatic gland
apocrine gland
sebum
a.)lubricates the surface of the skin and hair
b.)consists of cell fragments and fatty substances
c.)in excess may cause seborrhea
d.)all of these
all of these
the rule of nines is helpful clinically in
a.)diagnosing skin cancer
b.)estimating the extent of a burn
c.)estimating how serious a cancer
d.)preventing acne
estimating the extent of a burn
all the following are functions of the skin except:
a.)excretion of body wastes
b.)insulation
c.)protection from mechanical damage
d.) site of vitamin A synthesis
site of viatmin A synthesis
the skin has two distinct regions. the superficial layer is the _______ and the underlying connective tissue is the _____.
epidermis and dermis
the most superficial layer of the epidermis is the:
a.)stratum basale
b.)stratum spinosum
c.)stratum granulosum
d.)stratum corneum
stratum corneum
thick skin of the epidermis contains ____layers.
5
____ is a yellow_orange pigment found in the stratum corneum and the hypodermis.
a.)keratin
b.)carotene
c.)melanin
d.)hemoglobin
carotene
these cells produce a brown to black pigment that colors the skin and protects DNA from ultraviolet radiation damage.the cells are:
a.)dendritic cells
b.)keratinocytes
c.)melanocytes
d.)tactile cells
melanocytes
true or false
nails originate from the epidermis
true
the portion of a hair that projects from the scalp surface is known as the:
a.)bulb
b.)matrix
c.)root
d.)shaft
shaft
the ducts of _____ glands usually empty into a hair follicle but may also open directly on the skin surface
sebaceous
_____glands are found primarily in the genital and axillary areas
apocrine
four protective functions of the skin are:
prevent desiccation
prevents bacterial invasion
protects against thermal damage
protects against UV radiation
layer of translucent cells in thick skin containing dead kerantinocytes
stratum lucidum
two layers containing dead cells
stratum corneum and stratum lucidum
dermal layer responsible for fingerprints
papillary layer
vascular region of the skin
dermis as a whole, papillary layer and reticular layer
major skin area as a whole that produces derivatives (nails and hair)
epidermis as a whole
epidermal layer exhibiting the most rapid cell division
stratum basale
layer including scale like dead cells, full of keratin, that constantly slough off
stratum corneum
layer of mitotic cells filled with intermediate filaments
stratum spinosum
has abundant elastic and collagenic fibers
dermis as a whole, reticular layer
location of melanocytes and tactile (merkel) cells
stratum basale
area where weblike pre-keratin filaments first appear
stratum spinosum
layer of areolar connective tissue
papillary layer
the tough water repellent protein found in the epidermal cells is called
keratin
the pigments melanin and _______ contribute to skin color
carotene
a localized concentration of melanin is referred to as a _______
freckle
______ granules contain glycolipids that prevent water loss from the skin.
lamellar
fibers in the dermis are produced by:
fibroblasts
glands that respond to rising androgen levels are the __________glands.
Sebaceous and apocrine sweat
phagocytic cells that occupy the epidermis are called:
dendritic or langerhan cells
a unique touch receptor formed from a stratum basale cell and a nerve fiber is:
tactile or merkel disc
what layer is present in thick skin but not in the thin skin?
stratum lucidum
what cell to cell structures hold the cells of the stratum spinosum tightly together?
desmosomes
what substance is manufactured in the skin and plays a role i calcium absorption elsewhere in the body?
vitamin D
list the sensory receptors found in the dermis of the skin
free nerve endings (for pain, tempt), tactile corpuscles( for touch in hairless skin), lamellar corpuscles (for pressure)
define cyanotic: (cyanosis)
what does its presence imply?
a blue cast to the skin
inadequate oxygenation of the blood
produces an accumulation of oily material that is known as a blackhead.
sebaceous glands
tiny muscles, attached to hair follicles, that pull the hair upright during fright or cold.
arrector pili
sweat glands with a role in temperature control
sweat gland_eccrine
sheath formed of both epithelial and connective tissues
hair follicle
less numerous type of sweat producing gland, found mainly in the pubic and axillary regions.
sweat gland-apocrine
hair follicle
found everywhere on the body except the palms of hands and soles of feet (two from keys)
sebaceous glands
primarily dead/keratinized cells (two from key)
hair and nail
specialized nerve endings that respond to temperature, touch...
cutaneous receptors
secretes a lubricant for hair and skin
sebaceous glands
"sports" a lunule and cuticle
nail
with what substance in the bond paper does the iodine painted on the skin react?
the starch
what organ system controls the activity of the eccrine sweat gland?
nervous system (sympathetic division)
name three common fingerprint patterns:
loops, arches and whorls