INTEGUMENTARY
SYSTEM
INTEGUMENTARY Presentations
 Minimum
of 7 slides
 Will replace test
 All lab members must present
to receive full credit
 Provide medicinal and layman terminology
regarding the topic.
 LOTS of pics please…make them good
 One statistical bit of information regarding
the topic.
 Members will grade each other and class
will grade group!
The Skin (Basic Characteristics)
Waterproof
 Stretchable
 Washable
 Permanent-press
 Invisibly repairs small cuts, rips, and burns
 Guaranteed to last a lifetime with reasonable care
 Weighs on average between 9 and 11 pounds
(approx. 7%-15% of total body weight)
 Measures between 1.5 and 4 mm thick
 Thick skin –Does not have hair follicles or oil glands

 One
last interesting FACTOID about skin:
 Every
square centimeter of skin contains…
 70
cm of blood vessels,
 55 cm of nerves,
 100 sweat glands,
 15 oil glands,
 230 sensory receptors, and
 approximately 500,000 cells that are constantly dying
and being replaced (you lose 40 lbs of cells within your
lifetime)
 Function:
 Protection
 Structure:
 Composed
dermis
of two major regions: epidermis and
Epidermis
No Labeling YET!!!
 Composed
of epithelial
cells
 Not vascular
 Made up of 4 types of
cells
 Consists of 4-5 distinct
layers
 New epidermis is
regenerated every 2545 days
Cells of
the
Epidermis
Epidermal Cells
AKA:
The
Dendritic
Cell
4 Types of Cells:
 Keratinocytes
Produce
keratin,
waxy coating
 Melanocytes
Synthesize
pigment called
melanin
Protect cell from
UV radiation
Tactile Cell
AKA Merkel cell)
functions as a
sensory receptor
for touch
Langerhans’
cells
Macrophages that
help to activate
immune system
Layers of Epidermis
In thick skin (soles of feet and palms of hands) there
are five layers (strata); everywhere else has four
 Deep to Superficial:
 Stratum basale
 Stratum spinosum
 Stratum granulosum
 Stratum lucidum
(only present in
thick skin)
 Stratum corneum

Dermis
Strong, flexible
connective tissue
 Cell types:

Fibroblasts
 Macrophages
 Mast cells
 White blood cells


Binds the entire body
together

Your HIDE
Vascularized
 Hair follicles, oil glands,
and sweat glands
 2 major layers:

Papillary layer
 Reticular layer

Papillary Layer
 Highly
vascularized
 Borders the stratum
basale of epidermis
 Touch and pain
receptors
 On palms and soles,
these papillae lie atop
dermal ridges, which
produce whorled
epidermal ridges
(fingerprints)
Reticular Layer
80%
of dermis
layer
Collagen binds
water, helping to
hydrate the skin
Elastin fibers
give skin elasticity
The Hypodermis
 Known
as subcutaneous
tissue or superficial fascia
 Structure:
 Has
more adipose than
dermis
 Functions:
 Energy
reservoir
 Thermal insulation
 Hypodermic
Hypodermis
 Into
injections
subcutaneous tissue
since highly vascular
Subcutaneous Fat Distribution
PIGMENTS of the SKIN
Melanin
= brown
Carotene = orange
Hemoglobin = red
Carotene
Yellow to orange
pigment found in
certain plant
products
 Accumulates in
stratum corneum
and in adipose tissue
of hypodermis
 Most obvious in
palms and soles
where S. corneum is
thickest

Hemoglobin
 Red
pigment of red
blood cells (RBCs)
 Since Caucasian
people contain
relatively small
amounts of melanin,
their skin is nearly
transparent which
allows hemoglobin’s
color to shine
through
Sweat Glands
 Exist
all over skin
except nipples and part
of external genitalia
(more than 2.5
million/person)
 2 types:
 Eccrine
and apocrine
Eccrine Sweat Glands
Much
more
numerous
Most abundant
on palms, soles,
and forehead
Eccrine Sweat Glands
Secretion-called sweat-is
99% water, with some
salts, vitamin C, antibodies,
traces of urea, uric acid,
ammonia
 Also contains lactic acid,
which is the chemical that
attracts mosquitoes
 Normally of pH 4 to 6

Apocrine Sweat Glands
Most common in armpit and
anogenital regions
 Larger than eccrine glands
 Ducts empty into hair follicles
 Apocrine secretion has
generally same composition as
normal sweat, however it has
fatty acids and proteins which
makes it more viscous
 Odorless, however, when
decomposed by bacteria on
skin a “Body Odor” is created

Ceruminous Glands
 Modified
apocrine
glands found in the
lining of external ear
canal
 Secrete sticky
cerumen (earwax)
 Thought
to deter
insects (bitter flavor)
and block entry of
foreign particles
Mammary Glands
Specialized apocrine sweat gland
that secretes milk
 Exist in both men and women

Males – little mammary tissue
 Females – milk develops with
increase of hormones when
pregnant and after birth
 Prolactin
 Progesterone
 Estrogen

Nails





Modification of epidermis
Corresponds to hoofs or
claws of other animals
Contains hard keratin (like
hairs)
Clear, hard derivative of
stratum corneum
Growth rate is 1 mm/week



New cells added by mitosis in
the nail matrix
Growth zone at proximal edge
of nail
Structure:


Nail bed is skin on which
nail plate rests
Hyponychium is epithelium
of nail bed
THE END
TIME FOR THE
PRESENTATIONS