Skin and Body Membranes
ANATOMY & PHYSIOLOGY
EPITHELIAL MEMBRANES
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These are membranes that cover and line the
body (any area that is exposed to air).
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These include: cutaneous membranes (skin),
mucous membranes, and serous membranes.
MUCOUS MEMBRANES
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Line all body cavities
exposed to the exterior
(respiratory, urinary, and
reproductive tracts).
SEROUS MEMBRANES
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Line enclosed body cavities:
 Parietal lines the wall
 Visceral lines the organs

Serous fluid is between the
serous membranes (visceral
and parietal)
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The peritoneum lines the
organs of the abdominal
cavity.
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The pericardium surrounds
the heart and pleura
surrounds the lungs.
These act as protection and
lubrication (mostly).
CONNECTIVE TISSUE MEMBRANES
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Synovial
membranes:
surround the
joints and contain
lubricating fluid
(synovial fluid)

May contain sacs
called bursae
http://www.google.com/imgres?
INTEGUMENTARY SYSTEM (CUTANEOUS
MEMBRANE):
 Serves for homeostasis:
 a.k.a. skin
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Means covering

Contains keratin, a
protein
 Protects
(covers)
the body
 Regulates
body
temperature
 Prevents
H2O loss
 Secretes
some waste
 Location
of sensory
(some) equipment
STRUCTURE OF SKIN
1.
2.
Epidermis:
-outer layer of skin
-contain melanocytes
(cells that have
melanin, a pigment)
Dermis:
-inner layer of skin
-composed of
connective tissue (with
collagen & elastic
fibers), nervous tissue,
& blood
-thicker than epidermis
3.
Subcutaneous:
-a.k.a. as the
hypodermis
-Below the dermis
-Composed of loose
connective tissue and
adipose (fat)
-Binds the skin to
underlying organs
SECTION OF SKIN
http://www.google.com/imgres?
FUN FACTS ABOUT THE EPIDERMIS

Think about the saying “Beauty is only skin
deep.” Everything we see when we look at
someone is dead skin cells.

The average person sheds about 40 lbs of
dandruff (part of the epidermis) in a lifetime.

We grow a new epidermis about every 25-45
days.
FUN FACTS ABOUT THE DERMIS

Fingerprints, caused by dermal papillae (or
nipples), are genetically determined.

Since the dermal layer contains fat (adipose),
and as we age, we lose fat and the elasticity of
our skin, the dermal layer sags. This forms
wrinkles.
PIGMENTS THAT CAUSE SKIN COLOR:
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OTHER CAUSES OF SKIN COLOR:
Melanin (yellow, reddishbrown, or black)
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Carotene (orange-yellow)
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Hemoglobin (red)
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SKIN COLOR
Emotions
Illness (hypertension, fever,
inflammation, etc.)
Jaundice (yellow skin)
Bruising
Environment (UV rays)
Bloods vessels: If poorly
oxygenated, a bluish
appearance occurs. This is
called cyanosis.
APPENDAGES OF SKIN (ACCESSORY ORGANS):
Cutaneous glands: a.k.a. exocrine glands
 Sebaceous glands (oil secreting glands)
 Secrete
sebum (oil)
 Keeps hair and skin soft
 Protects skin and kills bacteria

Sweat glands
 a.k.a.
Sudoriferous glands
 Eccrine glands secrete sweat to regulate temperate
 Apocrine glands secrete sweat in emotions (stress,
pain, sex, and sometimes thermoregulation).
 Sweat is a mixture of water, urea, and salts.
APPENDAGES OF SKIN (ACCESSORY ORGANS):

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Hair protects skin
Hair follicles produce
hair
Located on all parts of
skin except: palms,
soles, lips, nipples, and
some reproductive
structures.

Nails protect skin and
sensory equipment
under skin.
http://www.google.com/imgres?
Warning: there are images on the next few slides
that MAY be disturbing!
Really.
IMBALANCES OF THE SKIN

Bedsores (pressure ulcers) occur when a
patient remains in one position too long. The
skin cells dies as a result of lack of blood
supply.
http://www.google.com/imgres?
IMBALANCES OF THE SKIN

Acne is caused by an infection of the
sebaceous glands.
http://www.google.com/imgres?
IMBALANCES OF THE SKIN
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A burn is tissue damage
(& cell death) caused by
some type of intense
heat.
There are 2 lifethreatening problems for
burn-victims: fluid loss
and infection
Pathogens (invaders like
bacteria or fungi) feed off
of destroyed skin.

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Doctors estimate fluid loss
(for burn victims) by using
the rule of nines.
This divides the body into
11 areas, each accounting
for 9% of the total body
surface area + 1%
representing the genital
area.
BURNS

First-degree burns: epidermis is damaged (think
sunburns).

Second-degree burns: epidermis and some dermal
tissue (upper layer) are damaged.
Blisters occur.
 This is painful.


Third-degree burns: destroys skin (a.k.a. fullthickness burns).
Nerve endings in the area of burned tissue are
destroyed (therefore, NOT painful).
 Skin grafting must be done to recover b/c skin will not
regenerate in these areas.

http://www.google.com/imgres?
SQUAMOUS CELL CARCINOMA:

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Quick growing skin cancer
that appears on epidermis.
Can metastasize (spread) to
lymph nodes (w/o treatment:
surgery or radiation).
Usually caused by sun
exposure.
Often found on ears, scalp,
lower lip, & back of the hand
SKIN CANCER
BASAL CELL CARCINOMA:
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Most common type of skin
cancer.
Slow growing, shiny round
nodules appear.
Usually caused by sun
exposure.
Rarely spread before
treatment (surgery).
Often found on face.
http://www.google.com/imgres?
SKIN CANCER
Malignant melanoma:

Cancer of melanocytes

Can be lethal

Usually appear spontaneously (however, can be caused
b/c a mole changes, DNA is damaged, genetic causes,
or sun damage).

Metastasizes quickly to lymph nodes and BVs (then to
other organs).

Treatment: surgery, radiation, and/or chemotherapy
MALIGNANT MELANOMA
ABCD recognition:
 (A) Asymmetry: pigment
is uneven
 (B) Border irregularity:
the lesion is not smooth
 (C) Color: the color of
the lesion varies within
the lesion (shades)
 (D) Diameter: the lesion
is larger than 6 mm
(pencil eraser)
http://www.google.com/imgres?
Look up in text or online! Know the following:
Athlete’s foot, boils, cold sores, dermatitis,
impetigo, and psoriasis.
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This slide show was developed by Dana Halloran,
Cardinal Mooney High School, Sarasota, FL.
Used with her personal permission,
adapted and amended by Rosa Whiting,
Manatee School for the Arts, Palmetto, FL.