What is the largest organ of the body
skin
what is the surface area of skin in an adult
2 square meters
what are the five things that make up the integumentary system
skin, hair, nails, smooth muscle of skin, glands of skin
what are the function of the skin
protection, excretion, temperature regulation, production of vitamin d, sensation, prevention of dehydration, storage of fat
what does the skin protect from
microorganisms, chemicals, ultraviolet light, injury
what does the skin excrete
sweat and oil
what does sweat consists of
excess water and waste
how does temperature regulation happen
insulation, sweating, and vasoconstriction/vasodilation
what tissue does the job of insulation
fat-adipose tissue
what kind of sensation does the skin feel
temperature, touch, pain
what are the layers of the skin
epidermis, dermis and hypodermis
the outermost layer of the skin is called
the epidermis
Name the five stratas of the epidermis
stratum basale, stratum spinsoum, stratum granulosum, stratum lucidum, stratum corneum
what is the deepest layer of the strata
stratum basale (stratum germinativum)
which stratum is present only in thick skin
stratum lucidum
which stratum is the top layers of dead cells
statum coreneum
each stratum consists of many layers of cell
true/false
true
what kind of tissue is the epidermis
stratified squamous non-ciliated epithelium
what are the four types of cells of the epidermis
keratinocytes, melanocytes, Langerhans, merkel
what do melanocytes do
produce a pigment called melanin
what does melanin do
impart skin color
what is melanin dependent on
exposure to sunlight, race and ethnicity, family history and genetics, hormones, pregnancy
which cells produce melanin
melanocytes
which cells impart skin color
melanin
which cells help in immune function
Langerhans
which cells are responsible for perception of sensation
merkel
where are merkel cells located
epidermis
where are Langerhans cell located
epidermis
where are melanocytes located
epidermis
which layer of skin does not have a blood supply
epidermis
how does the epidermis receive oxygen and nutrition
by the process of osmosis and diffusion.
what type of cells produce and store keratin
keratinocytes
where are keratinocytes located
epidermis
skin layer made of up connective tissue
connective tissue
which skin layer has a rich supply of nerves, blood vessels and lymphatics
dermis
what are the two layer of the dermis
papillary and reticular
what is the outer layer of the dermis called
papillary
what kind of tissue is the papillary layer made from
connective
which layer indents into the epidermis leading to dermal papillae
papillary layer
what helps to form prints
dermal papillae
what areas of the body leave a good print
fingertips, palms, soles
what is the deepest layer of the dermis called
reticular layer
what kind of tissue does the reticular tissue contain
connective tissue
which dermis layer has an abundance of collagen and elastic fiber
reticular layer
which dermis layer is responsible for the sagging and wrinkling of skin
reticular layer
what is the deepest layer of the skin
hypodermis
what's another name for the hypodermis
subcutaneous tissue or superficial fascia
which skin layer contains 50 percent body fat
hypodermis
which layers helps to anchor skin to the deeper tissue
hypodermis
name the effects of aging on the skin
blood flow to skin decreases
skin becomes thinner
loss of subcutaneous tissue (becomes thinner)
decrease of collagen and elastic fiber
sagging of skin
localized increase in melanocytes activity which lead to age spots
what is another name for hair
pili
where is hair produced
in the hair follicles
name the three parts of the hair
shaft-part we can see
root-just below the skin
bulb-deepest part
which tow parts of the hair are enclosed in the hair follices
lower part of the root and the bulb
What are the three concentric layers of keratinized cells
medulla, cortex, cuticle
central core, large cells with air spaces, contains soft keratin, absent in fine hairs
medulla
surronds the medulla
consists of squamous cells
cortex
outmost layers
single layer of squamous cells
cuticle
What is the average rate of hair growth per day
.3 mm
what is the type of hair that a baby is born with
lanugo
describe lanugo
fine, short, non-pigmented
what hair at birth turns into terminal hair
scalp, eyebrows and eye lashes
what is the hair called that is thick long and pigmented
terminal
at the birth the hair that is not terminal hair will turn into ______________
vellus hair
which hair is fine, medium and may or may not be pigmented
vellus hair
at puberty the vellus hair changes into _______ and forms on the _________
terminal and forms on the pubic, axillary, facial and body
what do people with red hair have a lot in their hair
iron
what do nails consist of
epidermis with a lot of hard keratin
what is the average rate of hair growth
.5mm/day
what actually forms the nail
the nail bed
what muscle contracts in response to cold or fright and leads to goose bumps
arrector pili
where is the arrector pili located
dermis
what are the three four glands in the skin
sweat, eccrine, apocrine, sebaceous
what is another name for the sweat glands
sudoriferous glands
which gland is more numerous and present all over the body
eccrine
which gland is in the palms, sole and forehead
eccrine
simple coil tubular gland
eccrine
which gland lies in the dermis
eccrine
what is sweat made of
water, nacl, vit C, waste (urea, uric acid, ammonia)
what is the approximate number of apocrine glands in our bodies
2000
where are the apocrine glands located
axillary and anogenital area
what gland produces sweat that contains a high amount of proteins and fat (more thick or viscos)
apocrine
which sweat gland leads to body odor
apocrine
whats another name for the oil glands
sebaceous glands
what are the places the sebaceous glands are not located
palms and soles
which glands are simple branched alveolar glands
sebaceous
which glands produce sebum
sebaceous
which glands contain a fatty substances
sebaceous
where do sebaceous glands secrete their fatty substance onto the skin
the hair follicle or directly onto the skin
what is the function of sebum
lubricate the skin
antiseptic effect
where are ceruminous glands located
external auditory meatus
what do ceruminous glands produce
cerumen (earwax)
which glands produce milk
mammary glands
which gland is part of the sweat gland
mammary
ceruminous and mammary glands are what kind of glands
apocrine