Integumentary System Slide 2 Statistics Covers the entire body.
Covers the entire body. Weighs between 9 to 11 lbs. Weighs between
9 to 11 lbs. Thickness of skin in some areas can be from 1.5 to 4
mm thick. Thickness of skin in some areas can be from 1.5 to 4 mm
thick. Flexible yet tough. Flexible yet tough. The #1 defense from
bacteria and fungi. The #1 defense from bacteria and fungi. Slide 3
Hypodermis (Not technically part of the skin) A.k.a. Superficial
fascia. A.k.a. Superficial fascia. Stores fat Stores fat Anchors
the skin (loosely) Anchors the skin (loosely) It is important that
we understand that the hypodermis anchors skin down loosely because
it allows some potential trauma to slide off of the body. It is
important that we understand that the hypodermis anchors skin down
loosely because it allows some potential trauma to slide off of the
body. Hypodermis will thicken when we gain weight. (In women,
thighs and breasts first, in men anterior abdomen) Hypodermis will
thicken when we gain weight. (In women, thighs and breasts first,
in men anterior abdomen) Slide 4 Hypodermis Slide 5 Hypodermis
anchors skin loosely Slide 6 Hypodermis thickening Slide 7
Epidermis The epidermis is made up of keritanized stratified
squamous epithelium. The epidermis is made up of keritanized
stratified squamous epithelium. Slide 8 Cell Types: Keratinocytes
Keratinocytes: cells that produce keratin. Keratinocytes: cells
that produce keratin. Keratin: fibrous protein that gives skin its
protective properties. Keratin: fibrous protein that gives skin its
protective properties. Slide 9 Cell Types: Melanocytes Melanocytes:
synthesize melanin. Have a web- like appearance. Found in the
deepest part of the epidermis. Melanocytes: synthesize melanin.
Have a web- like appearance. Found in the deepest part of the
epidermis. Melanin is created by the melanocytes, shipped up to the
keratinocytes through the spider-like arms of the melanocyte, and
deposited in the side of the nucleus of the keratinocyte that faces
towards the sun, which creates a barrier that protects the
keratinocytes nucleus from UV damage. Melanin is created by the
melanocytes, shipped up to the keratinocytes through the
spider-like arms of the melanocyte, and deposited in the side of
the nucleus of the keratinocyte that faces towards the sun, which
creates a barrier that protects the keratinocytes nucleus from UV
damage. Slide 10 Melanocytes Slide 11 Cell Types: Epidermal
dendritic cells A.k.a. Langerhans cells A.k.a. Langerhans cells
Spawn from bone marrow and work their way to the epidermis. Spawn
from bone marrow and work their way to the epidermis. Key part of
the immune system. Key part of the immune system. Slide 12
Langerhans cells Slide 13 Cell Types: Tactile cells A.k.a. Merkel
cells A.k.a. Merkel cells Very intimately close to Merkel discs
that act as receptors for the touch sense. Very intimately close to
Merkel discs that act as receptors for the touch sense. Merkel cell
carinoma Merkel cell carinoma Slide 14 Layers of the epidermis
Number of layers vary based on whether skin is thick or thin.
Number of layers vary based on whether skin is thick or thin.
Thick: 5 layers Thick: 5 layers Thin: 4 layers Thin: 4 layers Slide
15 Thick Skin Thick skins 5 layers: Thick skins 5 layers: Stratum
basale Stratum basale Stratum spinosum Stratum spinosum Stratum
granulosum Stratum granulosum Stratum lucidum Stratum lucidum
Stratum corneum Stratum corneum Examples of thick skin Examples of
thick skin Covers palms of hands Covers palms of hands Fingertips
Fingertips Feet Feet *Stratum= layer *Stratum= layer *Strata=
layers *Strata= layers Slide 16 Thin skin Thin skins 4 layers: Thin
skins 4 layers: Stratum basale Stratum basale Stratum spinosum
Stratum spinosum Stratum granulosum Stratum granulosum Stratum
corneum Stratum corneum Examples of thin skin: Examples of thin
skin: Everywhere else Everywhere else Slide 17 Stratum Basale
A.k.a. Basal layer A.k.a. Basal layer Deepest layer and attached to
the dermis. Deepest layer and attached to the dermis. As these
cells divide, they push the cells above them closer to the surface
of the skin, and force the other layers to mature into fully formed
keratinocytes faster. As these cells divide, they push the cells
above them closer to the surface of the skin, and force the other
layers to mature into fully formed keratinocytes faster. Slide 18
Stratum spinosum Several layers thick. Contains a web-like system
of intermediate filament designed to resist tension. Several layers
thick. Contains a web-like system of intermediate filament designed
to resist tension. Looks like prickly spiked balls. Looks like
prickly spiked balls. Slide 19 Stratum granulosum Thin layer (3-5
layers). Thin layer (3-5 layers). This is where the bulk of
keratinization occurs. Each of the layers in this stratum will
start to look very different. This is where the bulk of
keratinization occurs. Each of the layers in this stratum will
start to look very different. Cells flatten; nuclei and organelles
disintegrate. Cells flatten; nuclei and organelles disintegrate.
Forms lamented and keratohyaline cells. Forms lamented and
keratohyaline cells. Keratohyaline cells: helps form keratine in
the upper layers Keratohyaline cells: helps form keratine in the
upper layers Lamented cells: creates water resistant glycolipids
that fill extracellular spaces in the cell. Lamented cells: creates
water resistant glycolipids that fill extracellular spaces in the
cell. Slide 20 Stratum lucidum Consists of two clear flat dead cell
layers. Uses keratin to bind together in a cable like array. (thick
skin only) Consists of two clear flat dead cell layers. Uses
keratin to bind together in a cable like array. (thick skin only)
Slide 21 Stratum corneum Outermost layer. (20-30 cell layers thick)
Outermost layer. (20-30 cell layers thick) Mostly all the cells of
this layer are dead. Designed to be durable and take damaged. Seen
most often flaking off as dandruff. Mostly all the cells of this
layer are dead. Designed to be durable and take damaged. Seen most
often flaking off as dandruff. Slide 22 Slide 23 End of Epidermis
Slide 24 Dermis Second major skin region. Made of strong connective
tissue. Second major skin region. Made of strong connective tissue.
Contains connective tissue proper cell types: Contains connective
tissue proper cell types: Fibroblasts Fibroblasts Macrophages
Macrophages Few mast cells Few mast cells Few white blood cells Few
white blood cells Slide 25 Major layers of the dermis Papillary
layer: Papillary layer: Made of areolar connective tissue. Made of
areolar connective tissue. Contains interwoven elastic and collagen
fibers. Contains interwoven elastic and collagen fibers. Contains
heavy amounts of blood vessels. Contains heavy amounts of blood
vessels. The loose connections of the tissue allows free movement
of defensive cells, like the WBCs and macrophages. The loose
connections of the tissue allows free movement of defensive cells,
like the WBCs and macrophages. Slide 26 continued The superior
surface contains peg-like projections called dermal papillae.
Others contain free nerve endings (pain receptors) and touch
receptors called Meissners corpuscules. The superior surface
contains peg-like projections called dermal papillae. Others
contain free nerve endings (pain receptors) and touch receptors
called Meissners corpuscules. On the hands and feet, papillae lay
on ridges called dermal ridges. The dermal ridges have ridges on
top of them called epidermal ridges. These ridges of skin are
collectively called friction ridges. On the hands and feet,
papillae lay on ridges called dermal ridges. The dermal ridges have
ridges on top of them called epidermal ridges. These ridges of skin
are collectively called friction ridges. Since sweat pores open on
these crests, we will leave behind a small film of sweat on
anything we touch. You know these as fingerprints. Since sweat
pores open on these crests, we will leave behind a small film of
sweat on anything we touch. You know these as fingerprints. Slide
27 Reticular layer The deeper and thicker of the two layers. The
deeper and thicker of the two layers. Course, irregular cell
arrangement, dense fibrous connective tissue. Course, irregular
cell arrangement, dense fibrous connective tissue. The cutaneous
plexus, a layer of blood vessels that give nutrients to this layer,
are between this layer and the hypodermis. The cutaneous plexus, a
layer of blood vessels that give nutrients to this layer, are
between this layer and the hypodermis. Slide 28 continued In
certain areas, skin that has less dense regions of the collagen
fibers will form what is called cleavage. In certain areas, skin
that has less dense regions of the collagen fibers will form what
is called cleavage. When surgeons make an incision parallel to
these lines, the skin gapes less and heals faster. When surgeons
make an incision parallel to these lines, the skin gapes less and
heals faster. Slide 29 continued Flexure lines are dermal folds
that occur near joints where the dermis is firmly anchored to
deeper structures. (look at the creases on the palms of your hands)
Flexure lines are dermal folds that occur near joints where the
dermis is firmly anchored to deeper structures. (look at the
creases on the palms of your hands) The dermis is folded due to the
fact that skin cannot slide enough to conform to the joints in your
hands. The dermis is folded due to the fact that skin cannot slide
enough to conform to the joints in your hands. Slide 30 Slide 31
End of Dermis End of Dermis Slide 32 Skin Color Three major
pigments make up the skin: Three major pigments make up the skin:
Melanin Melanin Carotene Carotene Hemoglobin Hemoglobin Slide 33
Melanin Only one of the three pigments made in the skin. Only one
of the three pigments made in the skin. Polymer of tyrosine amino
acids. Polymer of tyrosine amino acids. Passed up from melanocytes
to keratinocytes. Passed up from melanocytes to keratinocytes.
Found only in the deepest layers of the epidermis. Found only in
the deepest layers of the epidermis. Slide 34 Melanin Slide 35
Human skin color Skin tone: Skin tone: Darker skinned people are
distributed more around the equator. This is due to more direct
contact from the suns rays. Darker skinned people are distributed
more around the equator. This is due to more direct contact from
the suns rays. Their skin produces more melanin to protect their
skin cells from harmful UV rays. Their skin produces more melanin
to protect their skin cells from harmful UV rays. Slide 36 Carotene
Yellow-orange pigment found in certain plants like carrots.
Accumulates in the stratum corneum, and in fatty layers of the
hypodermis. Yellow-orange pigment found in certain plants like
carrots. Accumulates in the stratum corneum, and in fatty layers of
the hypodermis. In asian people, the yellowish tint to their skin
is due to varying levels of melanin and carotene. In asian people,
the yellowish tint to their skin is due to varying levels of
melanin and carotene. Slide 37 Carotene Carotene Slide 38
Hemoglobin The pinkish hue of hemoglobin is most evident in
Caucasian people due to the fact that they lack very much pigment,
allowing the reddish tint of hemoglobin to shine through the skin.
The pinkish hue of hemoglobin is most evident in Caucasian people
due to the fact that they lack very much pigment, allowing the
reddish tint of hemoglobin to shine through the skin. Heme group
Slide 39 End of skin color End of skin color Slide 40 Glands
Appendages (added attachment) of the skin, glands function to cool
down the body and expel wastes. Appendages (added attachment) of
the skin, glands function to cool down the body and expel wastes.
Slide 41 Sudoriferous Sweat Glands All over the skins surface with
the exception of the nipples and part of the external genitalia.
All over the skins surface with the exception of the nipples and
part of the external genitalia. Slide 42 There can be upwards of 3
million of these glands on a body. There can be upwards of 3
million of these glands on a body. When myoepithelial cells
contract, they squeeze out the secretion and forces the sweat to
the skin surface. When myoepithelial cells contract, they squeeze
out the secretion and forces the sweat to the skin surface. Slide
43 Eccrine sweat glands A.k.a. merocrine sweat glands. A.k.a.
merocrine sweat glands. Most abundant on the palms of the hands,
forehead, and soles of the feet. Most abundant on the palms of the
hands, forehead, and soles of the feet. The secretory part is deep
in the dermis, and pores (channels) allow for secretions to be
brought to the surface. The secretory part is deep in the dermis,
and pores (channels) allow for secretions to be brought to the
surface. The secretion from eccrine glands are what we call sweat.
The secretion from eccrine glands are what we call sweat. Slide 44
Contains small amounts of uric acid (also found in urine), which
alters the pH of sweat to between 4-6. Contains small amounts of
uric acid (also found in urine), which alters the pH of sweat to
between 4-6. Major role is to prevent overheating of the body.
Major role is to prevent overheating of the body. Slide 45 Apocrine
glands Confined to the axillary (under arm) and anogential (genital
region) areas. Confined to the axillary (under arm) and anogential
(genital region) areas. Begin functioning around puberty. Begin
functioning around puberty. Slide 46 Ceriminous glands Modified
apocrine glands. Modified apocrine glands. Secrete sebum in the ear
canal. Secrete sebum in the ear canal. Mix with sebacous glands to
form ear wax. Mix with sebacous glands to form ear wax. Slide 47
Mammary glands Secrete milk. Secrete milk. Also included as a part
of the female reproductive system. Also included as a part of the
female reproductive system. Slide 48 Oil based glands Slide 49
Sebaceous Glands (oil glands) Branched alveolar glands. Found
everywhere except the thick skinned parts of the hands and feet.
Branched alveolar glands. Found everywhere except the thick skinned
parts of the hands and feet. Most are found in hair follicles. Most
are found in hair follicles. gland store oils, and become so
stuffed with oil, it explodes! (holocrine gland) gland store oils,
and become so stuffed with oil, it explodes! (holocrine gland)
Lipids plus cell fragments= sebum Lipids plus cell fragments= sebum
Slide 50 What happens when sebaceous glands become clogged up? If a
sebaceous gland becomes clogged with sebum, the a whitehead may
form. If a sebaceous gland becomes clogged with sebum, the a
whitehead may form. If that material oxidizes and dries, then a
blackhead is formed. If that material oxidizes and dries, then a
blackhead is formed. Slide 51 The inflammation of the sebaceous
gland along with a pustule or cyst is called acne. The inflammation
of the sebaceous gland along with a pustule or cyst is called acne.
Slide 52 End glands End glands Slide 53 Hair Hair covers almost all
of the body. Hair covers almost all of the body. Functions to keep
us warm and help us sense insects before they bite us. Functions to
keep us warm and help us sense insects before they bite us. Hair on
the head guards against physical trauma, heat loss, and sunlight.
Hair on the head guards against physical trauma, heat loss, and
sunlight. Slide 54 Examples of hair Slide 55 Hair structure Pili
(hair) consists largely of dead keratinized cells. Pili (hair)
consists largely of dead keratinized cells. Hard keratin prominent
in hair. Hard keratin prominent in hair. Allows hair to be tougher
and more durable, and individual cells do not flake off. Allows
hair to be tougher and more durable, and individual cells do not
flake off. Slide 56 Hair anatomy Consists of a shaft, and a root.
The root is the active growing region. Consists of a shaft, and a
root. The root is the active growing region. Flat and ribbon like
hair structure results in kinky hair. Flat and ribbon like hair
structure results in kinky hair. Slide 57 If the follicle is round,
then the hair will appear wavy. If the follicle is round, then the
hair will appear wavy. Slide 58 Hair Contains three keratinized
layers of cells. Contains three keratinized layers of cells. Middle
layer called the medulla, consists of large cells and spaces.
Middle layer called the medulla, consists of large cells and
spaces. The cortex surrounds the medulla, and consists of several
layers of flattened cells. The cortex surrounds the medulla, and
consists of several layers of flattened cells. The cuticle is the
outermost layer that forms by having a single layer of cells
overlap each other like shingles on a roof. The cuticle is the
outermost layer that forms by having a single layer of cells
overlap each other like shingles on a roof. Slide 59 Slide 60 Hair
root The root of the hair contains the hair bulb, which is beneath
the skins surface. The root of the hair contains the hair bulb,
which is beneath the skins surface. The hair bulb has a sensory
nerve ending wrapped it called the hair follicle receptor, which
allows transmissions of messages to the brain when a stimulus is
applied. The hair bulb has a sensory nerve ending wrapped it called
the hair follicle receptor, which allows transmissions of messages
to the brain when a stimulus is applied. Slide 61 Hair follicle
Wall is composed of connective tissue root sheath, which is derived
(came from) dermal tissue. Wall is composed of connective tissue
root sheath, which is derived (came from) dermal tissue. This is an
invagination This is an invagination in the epidermis formed by the
inner root sheath. Slide 62 The arrector pilli A muscle associated
with the hair follicle. A muscle associated with the hair follicle.
Most hairs grow in at an angle. The arrector pilli pull hairs into
an upright position. Most hairs grow in at an angle. The arrector
pilli pull hairs into an upright position. When the body cools too
low, the arrector pilli is responsible for creating bumps on the
skin surface. When the body cools too low, the arrector pilli is
responsible for creating bumps on the skin surface. Slide 63 Not
very useful in humans because we have short hairs, but in long
haired animals it allows them to retain heat. Not very useful in
humans because we have short hairs, but in long haired animals it
allows them to retain heat. Slide 64 Types of Hair Vellus hair-
thin hair. Mostly on children and adult females. Vellus hair- thin
hair. Mostly on children and adult females. Slide 65 Types of Hair
Terminal hair-Longer thicker hair, found on eyebrows and scalp.
Terminal hair-Longer thicker hair, found on eyebrows and scalp.
Slide 66 Growth Rates of Hair Varies, but the greatests rates of
hair growth occur on the scalp and armpits. Varies, but the
greatests rates of hair growth occur on the scalp and armpits. The
hair on the legs can be stimulated by shaving, due to a
physiological response to the cold. (Even when it is hot) The hair
on the legs can be stimulated by shaving, due to a physiological
response to the cold. (Even when it is hot) Slide 67 Growth of hair
is the fastest between your teens through your 40s. Growth of hair
is the fastest between your teens through your 40s. Male pattern
baldness is a genetic sex- linked trait, and doesnt just happen.
Male pattern baldness is a genetic sex- linked trait, and doesnt
just happen. Slide 68 End hair Slide 69 Nails Scale like
modification to hands. Protective covering for the fingers, allows
us to pry open objects. Scale like modification to hands.
Protective covering for the fingers, allows us to pry open objects.
Nails correspond to claws and hooves in other animals. Nails
correspond to claws and hooves in other animals. Slide 70 The Nail
bed In the nail bed, the thickened portion is called the nail
matrix. The nail matrix is the place where the nail grows. In the
nail bed, the thickened portion is called the nail matrix. The nail
matrix is the place where the nail grows. Slide 71 Anatomical terms
for the nail Nail folds- lateral parts of the nail that the skin
folds over. Nail folds- lateral parts of the nail that the skin
folds over. Eponychium- the nail body (cuticle) Eponychium- the
nail body (cuticle) Hyponchium- below the nail. Hyponchium- below
the nail. Slide 72 End Nails End Nails Slide 73 Functions of the
Integumentary system Protection Protection Body temperature
regulation Body temperature regulation Cutaneous sensation
Cutaneous sensation Metabolic function Metabolic function Blood
reservoir Blood reservoir Excretion Excretion Slide 74 Protection
Chemical barriers: i.e. melanin in the skin. Chemical barriers:
i.e. melanin in the skin. The acid mantle, due to a lower pH of the
skin, the skin tends to ward off or slow down most bacterial
growth. The acid mantle, due to a lower pH of the skin, the skin
tends to ward off or slow down most bacterial growth. Skin produces
an antibiotic called defensins, which fight off microbial growth.
Skin produces an antibiotic called defensins, which fight off
microbial growth. Cathelicidians- wounded skin produces a multitude
of peptides called cathelicidians, which fight off bacteria
(especially streptococcus) Cathelicidians- wounded skin produces a
multitude of peptides called cathelicidians, which fight off
bacteria (especially streptococcus) Slide 75 Physical barriers
Provides a physical continuity to skin. Thicker skin could be
beneficial, but we would lose softness and agility. Provides a
physical continuity to skin. Thicker skin could be beneficial, but
we would lose softness and agility. Glycolipids in the epidermis
prevent diffusion directly through the skin. Prevents water loss
and water entry in the skin. Glycolipids in the epidermis prevent
diffusion directly through the skin. Prevents water loss and water
entry in the skin. Slide 76 Biological barriers Includes DNA,
macrophages on the dermis and dendritic cells of the epidermis.
Includes DNA, macrophages on the dermis and dendritic cells of the
epidermis. Electrons in DNA can absorb UV rays to a degree, which
allows for DNA to resist some of sun the suns rays. Electrons in
DNA can absorb UV rays to a degree, which allows for DNA to resist
some of sun the suns rays. Slide 77 Body Temperature Regulation
Under normal conditions, the body will lose 0.5L of sweat per day.
Under normal conditions, the body will lose 0.5L of sweat per day.
When your body temperature rises, your nervous system sends a
signal to your sweat glands to begin perspiration. When your body
temperature rises, your nervous system sends a signal to your sweat
glands to begin perspiration. Slide 78 Cutaneous sensation
Cutaneous sensory receptors (part of the nervous system). Allows us
to sense when there is a change in the environment, like the wind
blowing. Cutaneous sensory receptors (part of the nervous system).
Allows us to sense when there is a change in the environment, like
the wind blowing. Slide 79 Metabolic functions The skin uses a
modified form of cholesterol, along with the suns rays, to create a
vitamin D precursor to ultimately create vitamin D. The skin uses a
modified form of cholesterol, along with the suns rays, to create a
vitamin D precursor to ultimately create vitamin D. Slide 80 Blood
reservoirs The skin can hold up to 5% of the bodys blood. The skin
can hold up to 5% of the bodys blood. When the blood vessels
constrict, excess blood may be forced out of the blood vessels and
into the skin, making you look flushed. When the blood vessels
constrict, excess blood may be forced out of the blood vessels and
into the skin, making you look flushed. Slide 81 Excretion Ammonia
and uric acid are removed from the body through sweat. Ammonia and
uric acid are removed from the body through sweat. Slide 82 End
Functions Slide 83 Imbalances in the skin (Bad stuff) Skin cancer-
damage to the p53 gene, which is a tumor supressing gene. Usually
requires frequent dermal irritation. (frequent tanning, sun burn)
Skin cancer- damage to the p53 gene, which is a tumor supressing
gene. Usually requires frequent dermal irritation. (frequent
tanning, sun burn) Slide 84 Basal cell carcinoma- appears shiny and
dome shaped. Accounts for 80% of all skin cancers. Sun exposed
areas usually where lesions occur. Relatively slow growth. Unlikely
to metastasize. Basal cell carcinoma- appears shiny and dome
shaped. Accounts for 80% of all skin cancers. Sun exposed areas
usually where lesions occur. Relatively slow growth. Unlikely to
metastasize. Slide 85 Squamous cell carcinoma-grows rapidly and has
a higher metastasis rate. Usually scaly and red, slightly raised.
Squamous cell carcinoma-grows rapidly and has a higher metastasis
rate. Usually scaly and red, slightly raised. Slide 86 Melanoma-
cancer of melanocytes. Usually appears as an irregular black patch.
Melanoma- cancer of melanocytes. Usually appears as an irregular
black patch. Slide 87 Know your ABCDs A. Asymmetry- the sides of
the mystery mole do not match. A. Asymmetry- the sides of the
mystery mole do not match. B. Border irregularity- borders of mole
have indentations B. Border irregularity- borders of mole have
indentations C. Color- contains blacks, browns, blues, and other
colors. C. Color- contains blacks, browns, blues, and other colors.
D. Diameter- spot is larger than 6 mm in diameter. D. Diameter-
spot is larger than 6 mm in diameter. Slide 88 Burns 1 st degree-
least severe. Only epidermis is damaged. 1 st degree- least severe.
Only epidermis is damaged. Slide 89 Burns 2 nd degree-damage to the
epidermis and the upper layers of the dermis. Slim chance of
infection. Really hurts! 2 nd degree-damage to the epidermis and
the upper layers of the dermis. Slim chance of infection. Really
hurts! Slide 90 Burns 3 rd degree- Severe damage to epidermis,
dermis and even parts of the hypodermis. Skin must be removed. Does
not hurt. 3 rd degree- Severe damage to epidermis, dermis and even
parts of the hypodermis. Skin must be removed. Does not hurt. Slide
91 Things burn victims need to worry about Over heating Over
heating Limited mobility Limited mobility
