Integumentary System
Epidermal cells produce _____________ , which is converted to _______________, which aids in _____________.
Vitamin D3, Calcitriol, Calcium absorption
What does keratohyalin promote
aggregation and cross-linking of keratin fibers in neighboring cells
what does the dermis do
anchors epidermal accessory structures (hair follicles, sweat glands) and provides oxygen and nutrients to the epidermis
what are the two types of sweat glands
apocrine and merocrine (eccrine) glands
what is the hypodermis
area of loose connective tissue deep to the dermis
what does the papillary layer (outer layer) made of
areolar connective tissue
where are apocrine sweat glands found
armpits, around nipples, and groin
when do merocrine glands become active
at birth
where does hair production begin
at the base of the hair, deep in the dermis
is the epidermis vascular or avascular?
avascular - no blood vessels
what are the functions of merocrine sweat glands
cools skin, excretes water and electrolytes, flushes microorganisms and harmful chemicals from skin
are the cells on the epidermis alive or dead
dead
what does the stratum lucidum do
decreases friction on cells and tissues below
where is the hair follicle located
deep in the dermis
what type of cells does the stratum basale contain
dendritic (langerhans) cells
what is keratohyalin
dense granules that promote dehydration of cells (nucleus and most organelles are destroyed)
what is the reticular layer (deep layer) made of
dense irregular connective tissue
what projects up between epidermal ridges in the papillary layer of the dermis
dermal papillae
where are tactile corpuscles located
dermal papillae
how are the layers of keratinocytes bound together
desmosomes
where do sebaceous follicles discharge
directly onto the skins surface
how is the stratum spinous produced
division of stem cells (basal cells) in the stratum basale
what is an example of when cyanosis would occur
drowning, choking, and a severe asthma attack
what do ceruminous glands protect
eardrums
how many layers of keratinocytes are in the stratum spinosum
eight to ten layers
what type of cells produce vitamin d3
epidermal cells
where does carotene accumulate
epidermal cells and fatty tissues of the dermis
what does the stratum basale form
epidermal ridges
what type of tissue is the hair follicle
epithelial tissue
how often is the stratum corneum replaced
every 2 weeks
what do epidermal ridges cause
fingerprints
what is dermal papillae responsible for
fingerprints
what is the stratum lucidum made of
flat, densely packed cells filled with keratin
how is hair color determined
genetics
what are ceruminous glands
glands that produce cerumen (earwax)
what are mammary glands
glands that produce milk in response to prolactin (hormone)
what can the arrestor pili produce
goose bumps
what are simple branched alveolar glands associated with
hair follicles
what does the hair bulb produce
hair matrix
where are terminal hairs located
head, eyebrows, and eyelashes and other parts of the body after puberty
how is the stratum basal attached to the basement membrane
hemidesmosomes
what type of needles are used to inject into the hypodermis
hypodermic needles
where are Merkel cells found
in hairless skin such as the palms of the hands and the soles of the feet
when do epidermal cells produce vitamin d3
in the presence of UV radiation
where is melanin located
in transport vesicles (melanosomes)
what does dermal papillae do
increase surface ares and strengthens the bonds
what is an example of something injected into the hypodermis
insulin
what is insensible perspiration
interstitial fluid lost by exasperation through the stratum corneum
where is insulin injected
into the fat - subcutaneous
what is the arrestor pili muscle
involuntary smooth muscle the is connected to the hair root
what happens when oxygen is bound to hemoglobin
it is bright red (no oxygen -deep dark, reddish, blueish color)
what does the stratum granulosum produce
keratin and keratohyalin
what are the most abundant cells found in the epidermis
keratinocytes
what can melanin be transferred to
keratinocytes
what does the reticular layer contain
larger blood vessels, lymphatic vessels, nerve fibers, collagen, and elastic fibers
what does sebum (oil) contail
lipids
what does the skin store
lipids
where is cyanosis first seen
lips, and under the nails
what organs convert vitamin d3
liver and kidneys
what do sebaceous glands do
lubricate hair and control bacteria
what does sebum do
lubricates and protects the epidermis, inhibit bacteria
what does keratin do to cells
makes cells water resistant and resistant to abrasion
what does the skin produce
melanin and keratin
what is a melanocyte
melanin cell
what is hair color produced by
melanocytes near the hair papilla
why do some people have darker skin tones
melanocytes release melanosomes more superficially
what is a type of cancer that originated in melanocytes
melanoma (skin cancer)
where do sensory receptors provide information to
nervous system
what does the hair follicle produce
nonliving hairs
what is a sebaceous gland
oil gland
where does keratinization occur
on all exposed skin surfaces except the eyes
what is carotene
orange-yellow pigment found in orange vegetables
how many layers of keratinized cells are in the stratum corneum in thick skin
over 100 layers
where is thick skin present
palms of hands and soles of feet
where is hair not present on the body
palms, soles, lips, and portions of external genetalia, eyes
what is the hair shaft
part of the hair that extends past the surface (exposed)
what does the papillary layer supply
parts of the epidermis with nutrients and oxygen
What do melanocytes contain
pigment melanin (color of the skin)
what is skin color influenced by
pigments (carotene and melanin) and by blood circulation
what does a melanocyte produce and what does it protect the skin from
produces melanin; skin/tissues from sun damage
what is the function of hair
protects and insulates (from UV radiation), guards openings against particles and insects
what is keratin
protein that makes skin strong and water resistant
what do collagen and elastic fibers do
provide strength and flexibility; extent to papillary region and the hypodermis
what does the hypodermis so
provides insulation, is an energy reserve (stores fatty acids as triglycerides) and as a shock absorber and stabilizer
when do apocrine sweat glands become active
puberty
where are lamella red corpuscles located
reticular layer (deep)
what is the hypodermis connected to and by what
reticular layer of integument and by connective tissue fibers
what happens when there is an insufficient amount of vitamin D3 in the body
rickets can occur (weak bones that bow under pressure)
what does the skin get rid of
salts, water, and organic wastes (garlic, alcohol)
where are melanocytes found
scattered throughout the stratum basale
what do sebaceous glands secrete
sebum
what is the base of the hair follicle surrounded by
sensory nerves (root hair plexus)
what are lamellate corpuscles (pacinian corpuscles) used for
sensory of deep pressure and vibration
what are tactile corpuscles (Meissner's corpuscles) used for
sensory of light touch
what are the two types of sebaceous glands
simple branched alveolar glands, sebaceous follicles
what does the papillary layer contain
small capillaries (blood vessels), lymphatics, and sensory neurons
what are vellus hairs
soft, fine hairs
what is a exocrine gland
something that makes secretion
what do hemidesmosomes resemble
staple
what do apocrine sweat glands produce
sticky, cloudy secretions that break down and cause odors
what is the deepest layer of skin
stratum basale
what layer of skin do cells stop dividing, and start producing
stratum granulosum
the hypodermis is the site of what type of injections
subcutaneous
what is the hypodermis also called
subcutaneous
what happens to the skin when someone is hot
superficial blood vessels dilate causing the skin to redden
what do epidermal and dermal papillae create an increase of
surface area
what does calcitrol aid in
the absorption of calcium and phosphorous
what can damage to the epidermis increase
the amount of burn and blisters
where are merocrone (eccrine) sweat glands located
the body surface especially on the palms and soles
what are melanocytes responsible for
the brown pigment of the skin
what part of the skin is the stratum corneum
the exposed surface of the skin
what does osmosis affect
the flow through the stratum corneum in hypotonic water, water flows into the epidermis
what is keratinization
the formation of a layer of dead, protective cells filled with keratin
what are dendritic (langerhans) cells active in
the immune response
what is the hair root
the lower part of the hair beneath the surface
what are the two components of the dermis
the outer papillary layer and the deep reticular layer
what is melanin
yellow-brown or black pigment produced by melanocyte in the stratum basale
what is jaundice
yellow/orange skin color caused by a build up of bilirubin
Which of the following areas give the most insulation and shock absorption and allow us to store energy reserves.
Hypodermis
what do melanocytes protect the body from
UV radiation
how much interstate fluid is evaporated a day
.5 liters (500 mL)
how long does it take for a cell to move from the stratum basale to the stratum corneum
15 - 30 days
how many layers of keratinized cells are in the stratum corneum in thin skin
15 - 30 layers
How many layers of keratinocytes are found in the stratum granulosum
3 - 5 layers derived from the stratum spinosum
how many layers of skin are in thin skin
4
The epidermis in thin skin has _______ layers, the epidermis in thick skin has _______ layers.
4, 5
how many layers of skin are in thick skin
5
An asthmatic patient has a severe asthma attack and is unable to oxygenate their blood. Their skin may appear __________. This is referred to as _____________.
Blue, cyanosis
what does Ultraviolet Readiatio (UV) cause
DNA mutations and burns that lead to cancer and wrinkles
A patient has severe burns covering much of their body. Why would you be concerned with dehydration?
Disrupting the integrity of the epidermis increases insensible perspiration
The hair follicle is derived from __________ tissue and is located in the ___________.
Epidermal, Dermis
Melanin is produced by ___________. It's function is to protect from_________________.
Melanocytes, UV radiation
The outer layer of the dermis is the ________________. The inner layer is the ____________.
Papillary layer, Reticular layer
Which type of gland secretes an oily substance onto the hair?
Sebacceous gland
The sensory receptors in the dermis that sense light touch and are located in the dermal papillae are the...
Tactile corpuscles (Meissner's Corpuscles)
where are sebaceous follicle found
These are concentrated on the face, back, chest, nipples, and genetalia.
What is the purpose of the basal cells of the epidermis?
To divide to replenish the more superficial cells of the epidermis
what is the hair matrix
a layer of dividing basal cells that push the hair up and out of the skin
what is hemoglobin
a pigment found in red blood cells
what is cyanosis caused by
a severe reduction in blood flow or oxygenation
what does keratin make up
a tough, fibrous protein, makes up hair, nails, and skin
what does the arrestor pili muscle do
contracts when scared or cold causing the hairs on the skin to stand up
what does the stratum basal have many of
basal cells or germinative cells
where is the hypodermis located
below the integument
where is the dermis located
between the epidermis and subcutaneous layer (hypodermis)
what is hemoglobin responsible for
binding O2 and CO2 and carrying them through the blood
what do nerve fibers in the skin control
blood flow, gland secretions, sensory receptors
what happens to the skin when someone is cold
blood leaves the surface to keep the organs warm causing the skin to pale
what does the skin maintain
body temperature (insulation and evaporative cooling)
what is vitamin d3 converted into
calcitrol
what does the hair papilla contain
capillaries
how do nutrients and oxygen diffuse in the epidermis
capillaries in the dermis
what is vitamin D3 also known as
cholecalciferol
what is the hypodermis (subcutaneous layer) made of
connective and adipose tissue
where are velds hairs located
the surface of the body
why does the skin darken
there is an increase in melanin production
why are some people albino
they have a normal distribution of melanocytes, but do not produce any melanin
Is stratum lucidum found in thick or thin skin?
thick
is hair not present in thick or thin skin
thick skin
what are terminal hairs
thick, possibly heavy pigmented hairs
what do Merkel cells respond to
touch (trigger nervous system when compressed)
what are Merkel cells
touch receptors
what does the skin detect
touch, pressure, pain, and temperature
what does the skin protect
underlying tissues and organs
what are dermal papillae
upward, finger-like extensions of dermis
is the dermis vascular or avascular
vascular
what can carotene be converted into
vitamin A
what does the skin synthesize
vitamin d3
what is sensible perspiration
water excreted by sweat glands
what do merocrone secretions contain
water, salts, and organic compounds (peptide with antibacterial properties)
what are sweat glands
watery secretions
when does jaundice occur
when there are issues with the liver