Integumentary
System
Michelle Mason, Hunter
Eisenhower, Micaela
Lincoln, Liam Murray
What is the integumentary
system?
 Organ
system that protects the body from
damage
 Guards the body’s physical and
biochemical integrity
 Functions:

Waterproof, cushion, and protect deeper
tissues, excrete waste, regulate body
temperature, attachment point for sensory
receptors, vitamin D synthesis
The Skin
 The
skin is the body’s integumentary
system
 Largest of the body’s organ systems
 12% - 15% of body’s weight
 Is composed of a minimum of 3 layers:



Epidermis
Dermis
Hypodermis
Epidermis
 Outermost
layer composed of epithelial
cells
 Composed of 4 layers: stratum basale,
spinosum layer, stratum granulosum,
stratum corneum
 Has no blood supply and depends on
diffusion from dermal cells for metabolic
needs
Stratum Basal
 Bottom
most layer responsible for constantly
renewing epidermal cells
 Contains one row of undifferentiated columnar
stem cells that divide frequently


Half of the divided cells move to the next layer to
begin the maturing process
Other half stays in basal layer and divides over and
over to replenish basal layer
 Contains
melanocytes: the cells responsible for
creating melanin, the pigment responsible for skin
color
Spinosum Layer
 Cells
transferred here change from
columnar to polygonal
 Cells begin to synthesize keratin

Keratin is the key component in making up
the outer layer of skin, along with hair and
nails.
Stratum Granulosum
 Cells
here have lost their nuclei and are
characterized by dark clumps of
cytoplasmic material
 Here keratin proteins and water-proofing
lipids are produced and organized
Stratum Corneum
 Cells
here known as coreocytes and have
flattened out
 Cells here are composed of mainly keratin
protein which add strength but also allow
absorption of water
 Responsible for integrity and hydration of
skin
 Disruptions in this layer can result in a
variety of skin problems
Dermis

2 Layers



Dermis layer responsible for:



Stratum papillare
Stratum Reticulare
Cushioning body
Sense of touch
Made up of



Collagen
Elastic Fibers
Hair Follicles
Stratum Papillare
 Makes
up upper part of dermis
 It forms the sharp, wave shaped border of
the dermis
 The wavy surface increases the contact
with the epidermis
 Made of loose connective tissue
 Connects the dermis to the epidermis
Stratum reticulare
 Makes

Much thicker then the papillary
 The



up a lower part of the dermis
protein fibers give the layer
Strength
Extensibility
Elasticity
 Contains

Roots of hair, sebaceous glands, sweat
glands, receptors, nails, and blood vessels
Hypodermis
 Sometimes
referred to as the
Subcutaneous layer and the superficial
fascia
 The lowermost layer of the integumentary
system
 It contains larger blood vessels and nerves
than those in the dermis
 A major storage site for adipose tissue
Contents of The Hypodermis
 Cells



Fibroblasts
Adipose
Macrophages
 Subcutaneous


Fat
Layer of insulation to hold in heat
Assists in Homeostasis
Accessory Structures of the
Skin
 Sudoriferous
and sebaceous glands
 Hair and hair follicles
 Nails
Sudoriferous and Sebaceous
Glands


Sebaceous Glands: (oil glands) found
surrounding hair follicles and deposit sebum,
oily substance that lubricates the hair and
skin, onto the hair shaft
Sudoriferous glands: (sweat glands) located in
the dermis and secrete a watery substance
that is important in body temperature
regulation and excretion

Four types: Eccrine, apocrine, ceruminous, and
mammary glands
Eccrine & Apocrine Glands


Eccrine Glands: major sweat glands of the
human body; products contain mainly
water, salts, and nitrogen-containing wastes
Apocrine Glands: don’t become active
until after puberty; found only in the axilla,
genital area, and areolae of the nipple;
products contain lipids and proteins
Ceruminous & Mammary
Glands
 Modified
suderiferous glands
 Ceruminous Glands: Found in ear canal.
Produce a waxy substance (cerumen)
that prevents foreign substances from
entering the auditory canal.
 Mammary Glands: Found in breasts.
Synthesize and secrete milk after
appropriate hormonal stimulation.
Integumentary Illnesses
 Sunburn
 Athlete’s
 Albinism
 Acne
 Herpes
 Blisters
 Rashes
foot
Souces





http://en.wikipedia.org/wiki/Integumentary_syste
m
http://www.emc.maricopa.edu/faculty/farabee/
biobk/biobookintegusys.html
http://www.britannica.com/EBchecked/topic/189
836/epidermis
http://www.skinscience.com/_int/_en/topic/topic_sousrub.aspx?t
c=SKIN_SCIENCE_ROOT%5EAN_ORGAN_REVEALED
%5ETHE_DERMIS&cur=THE_DERMIS
http://en.wikipedia.org/wiki/Subcutaneous_tissue