BODY MEMBRANES AND
THE SKIN
INTRO TO SKIN AND THE INTEGUMENTARY SYSTEM
BODY MEMBRANES: 2 TYPES
• Functions (overall)—Predict first! Write down in your
notes!
• Cover body surfaces
• Line body cavities
• Form protective and lubricating sheets around organs
• Epithelial membranes and connective membranes
• Types classified by their tissue makeup
QUESTION:
• What are the 4 types of tissues?
TYPE #1: EPITHELIAL MEMBRANES
• AKA covering and lining membrane
• Contains both epithelial tissue and connective
tissue
• Since it contains more than 1 type of tissue, what could
these membranes be considered as?
• Organs!
• Contains 4 sub-categories
EPITHELIAL MEMBRANE: CUTANEOUS
• Cutaneous membranes
• AKA your skin!
• “dry” membrane and
exposed to air
• Stratified squamous
epithelium (epidermis)
PLUS dense connective
tissue (dermis)
• Protection
QUESTION:
• What does “epi” mean?
a) Below
b) On top of
c) Within
EPITHELIAL MEMBRANE: MUCOUS
• Mucous Membrane
• Lines all body cavities
open to the exterior
•
•
•
•
Respiratory
Digestive
Urinary
Reproductive tracts
• “wet” membrane with
secretions of mucous or, in
the case of the urinary
system, urine
• Most have stratified
squamous epithelium OR
simple columnar
epithelium PLUS loose
connective tissue
• Function: protection,
lubrication, secretion,
absorption
THINK-PAIR-SHARE
• Give 1 similarity and 1 difference between
cutaneous and mucous membranes
• WRITE THIS IN YOUR NOTES!
EPITHELIAL MEMBRANE: SEROUS
• Serous Membranes (serosa)
• Lines body cavities closed to the
interior
• Heart
• Lungs
• Abdominal organs
• Simple squamous epithelium PLUS
areolar connective tissue (loose
connective tissue) with serous
fluid in between.
• Function: produce lubricating
fluid that reduces friction
A QUICK NOTE ABOUT SEROSA....
• It ALWAYS comes in 2 layers
• Visceral (inner) and parietal (outer) layers
• Visualize:
• There is fluid in between the two layers to allow for the
membranes to easily side past one another
• Think about the organs that are constantly in motion
• Structure RELATES to function!
THINK-PAIR-SHARE
• Name 1 similarity and 1 difference between
mucous and serous membranes
• WRITE THIS IN YOUR NOTES!
CONNECTIVE MEMBRANE:
SYNOVIAL
• Synovial Membranes
• Soft aerolar connective
tissue
• NO epithelial tissue
• Found in joints
• Provide a smooth
surface and lubricating
fluid
• Cushions organs moving
against one another
• Also form small sacs
called bursae
QUESTION:
• Which of the following contains both connective
AND epithelial tissue?
a) Serous membranes
b) Synovial membrane
c) Cutaneous membrane
THINK-PAIR-SHARE
• Give 1 similarity and 1 difference between serous
and synovial membranes
• WRITE THIS IN YOUR NOTES
STOP!
• Worksheet about membranes
• Fill in the table and color the pictures!
• With the table, be general when it comes to tissue types
• Make study materials:
• Make a graphic organizer, flashcards, start rewriting your
notes
• I will be around to check what you have made. This is your
ticket out the door!
SUMMARIES
• These people need to write me a summary about
cell division (found in you book)
• 5th:
• Aunna, Annika, Zak, Erika, Jasmin, Monica, Maria, Simona
• 7th:
• Larry, Marissa, Shelby, Courtney, Dakota, Landon, Caleb, Jessica
WARM UP/REVIEW
• Create a web of the body membranes (be
general)
SKIN!
• Cutaneous membrane
• Basic functions--predict first! (write down in your notes!
• Protection
• From mechanical damage (bumps), chemical damage, bacteria,
UV, thermal damage, desiccation
• Heat retention
• Excretion of urea and uric acid
• How?
• Sweat! (keep in mind that that is the same type of stuff that is in our
urine.....)
• Synthesize vitamin D
STRUCTURE OF THE SKIN
• Split up into 2 parts:
• Epidermis
• Epithelial tissue
• Dermis
• Connective tissue
• The dermis and epidermis are
firmly connected, but can
separate if subjected to
rubbing (friction) or a burn
• Fluid can then accumulate
between the two layers and
form a.....
• BLISTER!
JUST AN FYI
• If you get a blister, you
should NOT pop it!
• The fluid within is a
protective layer because
there is delicate skin that is
being formed underneath
the blister
• If you pop your blister, you
will just irritate it more, put
yourself at risk for infection,
and limit your footwear
possibilities
EPIDERMIS
• Split up into 5 zones known as strata
TRUE OR FALSE
• The epidermis has great access to blood supply to
supply it with a ton of nutrients.
• HINT: think about the tissue that composes the epidermis
DEEP TO SUPERFICIAL
• All epidermal cells are keratinocytes
• Keratinocytes contain keratin
• A protein that makes cells hard so they are resistant to damage and
desiccation
• Stratum Basale
• Cells have most adequate nourishment
• Why?
• Lies closest to the connective tissue layer (dermis); epidermis is avascular
• Constantly undergoing cellular division and the daughter cells are pushed
upward (superficial), away from the nutrients
• Stratum Spinosum
• Cells take on a spindley apprearance
• Develop desmosomes (what were those things again??)
• Stratum Granulosum
• Keratin is packed into little “packets” or granules
DEEP TO SUPERFICIAL
• Stratum Lucidum
• Cells flatten, become very keratinized (hardened), and die
• Appear to be clear when looked at under a microscope
• Think: What does it mean to be “lucid”?
• Stratum Corneum
• Amounts for ¾ of epidermal cells thickness
• These are shinglelike dead cells that are shed on a regular
basis
• Essentially sacks of keratin
LET’S COME UP WITH A MNEMONIC
• Take a few minutes to come up with a mnemonic
with your partners to help you remember the layers
of the skin
• Mnemonic example: My Very Eccentric Mother Just
Served Us Nosehairs
• Mercury, Venus, Earth, Mars, Jupier, Saturn, Uranus, Neptune
• Apparently, Pluto isn’t a planet anymore 
MNEMONICS
Bottom to Top
•
•
•
•
•
Brithany,
Stop
Going
Late to
Class
Top to Bottom
•
•
•
•
•
Crazy
Lobsters
Gobble
Salmon
Butter
WHY DO WE LOSE CELLS FROM THE
STRATUM CORNEUM?
1. These cells are the farthest away from the nutrient
source
2. Keratin limits nutrient entry
QUESTION:
• What would happen if there was too much keratin
OR the stratum corneum wasn’t easily lost?
• Think-pair-share: write your prediction on the dry erase
board
DISEASE: HARLEQUIN ICHTHYOSIS
• Congenital disease
• You are born with it
• Caused by thickening of keratin
layer; stratum corneum builds up
• Causes cracked skin and “scales” that
can crack and inhibit movement
• These people have a huge risk of bacterial
infections getting into their skin
• http://www.youtube.com/watch?v
=dNOjs6NBgOM
OTHER CELLS
• Melanocytes
• Found in the stratum
basale
• Produce melanin
• Causes there to be
pigment
• Function: protect cells from
UV damage
• Natural sunscreen!
melanocy
te
• Why do we tan?
PREDICT
• Put your prediction in your notes
TANNING
• When the skin is exposed to sunlight, it stimulates the
melanocytes to produce more melanin
• More melanin=more protection of cells from UV damage
• Freckles and moles are patches of concentrated
melanin
QUESTION:
• Why are different races different colors?
• Talk with your partner and write a prediction on the white
board
WHY ARE THERE DIFFERENT SKIN
COLORS?
• Things to consider:
• Melanin protects from UV damage
• We still need UV to synthesize Vitamin D (makes bones
strong)
• Equatorial regions (think Africa and Mexico) have direct, intense sun
• Primary concern is protecting stratum basale from damaging UV rays
• What do you think about skin cancer prevalence?
• Europe does not have such direct sun
• We need the sun/UV rays for vitamin D
• Less melanin so we can soak up the sun to get that vitamin D, but we have an
increased risk of skin cancer
QUESTION:
• What if the melanocytes did not produce any
melanin?
ALBANISM
• A genetic disorder caused by a
defunct enzyme responsible for
helping the melanocytes
produce melanin
• The skin appears white or very
pale and usually have pale blue
eyes
• Also typically have poor vision
because melanin also helps in eye
development
PREDICT
• What do you predict the skin cancer frequency is
among people suffering from albanism?
• Think-pair-share
WARM UP
• Draw a picture that shows why there is an increased
cancer risk in lighter-skinned people
SOCIETAL CONSEQUENCES
• People with albanism typically face social and cultural
challenges
• Many cultures around the word have developed beliefs
regarding people with this disorder
• Tanzania and Burundi: rise in witchcraft-killings and body
parts sold to witchdoctors
• It is also thought in some African cultures that relations with an
albanistic woman can cure a man with HIV
• Some ethnic groups and geographical areas have an
increased susceptibility to albanism
• Ironically, these groups are places where people with albanism
are the most discriminated
• http://www.youtube.com/watch?v=zd7RRr5Eubg
PREDICT
• Vitamin D is important for having strong bones
• Our milk is “fortified” in vitamin D
• What you would happen if you were vitamin D deficient?
DISEASE: RICKETS
• “bendy” bones
• Usually occurs when we
do not get vitamin D
• people who live in
upper latitudes (Europe,
Canada) and have
dark complexions are
especially at risk
IN A NUTSHELL....
• You have 2 options:
1.
2.
You will get skin cancer if you are exposed to the sun
You will get rickets from staying out of the sun
STOP!
• Make a model of the cell using dried beans
• Each bean represents cells in a particular layer
WHEN YOU HAVE FINISHED YOUR
BEANS…..
• Create some study materials
•
•
•
•
•
Make some flashcards
Make a graphic organizer (I think a web might be nice…..)
Color-code your notes
Write some test questions
Draw some pictures in the margins
DERMIS
• Your “hide”
• Strong, stretchy, holds you together
• 2 major regions
• Papillary region
• Reticular layer
DERMIS: PAPILLARY LAYER
• Uppermost dermal layer
• Contains capillaries
• Nutrients!
• Question: which layer of epidermis
does it feed?
• Houses receptors
• Pain, touch
• Uneven surface
• Can be arranged in definite patterns
that are genetically determined
• Provide for grip
• What does this sound like?
STOP
• Look at your fingerprints! Use pencil lead.
• Question:
• The papillary layer is ___________ to the stratum basale
a) Superficial
b) Deep
c) Whodee-whattin?
RETICULAR LAYER
• Deepest skin layer
• Sits atop a layer of adipose tissue
• What is another word for adipose tissue?
• Contains:
• Blood vessels,
• Sweat/oil glands
• nerves
• Major protein: collagen
• Responsible for the toughness of the dermis; holds the cells
together
• “skin glue”
• Keeps skin hydrated
QUESTION
• Why do we get wrinkles?
• When we get older, we produce less collagen so our skin
becomes less elastic
• The adipose tissue in our face decreases
QUESTION:
• What would happen if there was a deficient
amount of collagen within the skin?
• Write a prediction on the white board
DISEASE:
DYSTROPHIC EPIDERMOLYSIS BULLOSA
(DEB)
• Caused by a mutation in
the gene responsible for
making collagen
• Skin is extremely fragile
• http://www.youtube.com/
watch?v=yJqe40_x-TA
HENNA VS TATTOOS
• We all know that tattoos are
permanent.
• Henna tattoos only last for a few
days or weeks.
• PREDICT:
• What layer of the skin is affected by
henna and real tattoos?
LET’S MAKE A DIAGRAM!!!
DRAW A PICTURE
• Make a simple drawing in your notes of the
epidermis and dermis
• Be sure to show each layer of the epidermis AND the dermis
DRAW A PIC OF THE SKIN
APPENDAGES OF THE SKIN
• Include cutaneous glands, hair and hair follicles, and
nails
• Mostly contained within the reticular dermal layer
APPENDAGES: CUTANEOUS
GLANDS
• All are exocrine glands
• They release their secretions onto the cell surface
• formed by the cells in the stratum basale
• Are later pushed down until they reside in the dermis
• 2 types:
• Sebaceous glands
• Sweat glands
SEBACEOUS (OIL) GLANDS
• Found everywhere except on
palms of the hands and soles of
the feet
• Ducts usually empty into hair
follicle
• Produce sebum
• Mixture of oily substances and
fragmented cells
• Keeps skin soft, moist, and prevents
hair from becoming brittle
• Also kills bacteria
• Become very active during
puberty (but of course you already
knew that  )
STOP
• “Biore strips”
THE SCIENCE OF ACNE
• Whiteheads
• Sebaceous gland’s duct
becomes blocked by
sebum
• Blackheads
• The sebum that blocks the
gland oxidizes and dries
SWEAT GLANDS
• AKA “sudoriferous” glands
• Come in 2 types
• Eccrine glands
• Found all over the body
• Produce sweat
• Water, salt, vitamin C, metabolic waste (UREA!!),
lactic acid
• Function:
• Maintain body temp
• Kill bacteria (sweat is slightly acidic)
• Apocrine glands
• Axillary and genital regions
• (where are those places in plain English?)
• Secretions are a bit different
• It is what makes you have stinky body odor
QUESTION
Sudoriferous glands produce:
a) Sebum
b) Sweat
c) Water
d) Whodee-whattin?
QUESTION
Sebaceous glands produce:
a) Sebum
b) Sweat
c) Water
d) Whodee-whattin?
CREATE A WEB
• Create a web in your notes detailing the
differences between sweat and sebaceous glands
HAIR
• Produced by a hair follicle in the dermis
• Made of keratinized dead material
• Root and shaft
• Your hair’s texture depends on the shape of the
shaft (the actual hair itself)
HAIR TYPES
• Oval shaft
• Wavy hair
• Flat shaft
• Curly hair
• Round shaft
• Straight, coarse hair
• Physics: Different hair
types will refract light
differently
GOOSEBUMPS, ANYONE?
• Attached to the hair follicle
in the dermal tissue, there is
a tiny muscle
• Arrector pili
• Nerves connect to it to
stimulate the hair to raise
• Question: what type of
muscle tissue is it?
• Smooth! You can’t control
your goosebumps!
QUESTION:
• What are the purpose of “goosebumps”? Why was
it evolutionarily important that we have this little
muscle?
• Talk it over with your partner!
UNDA THE DERMIS
• Under the dermis, we have the subcutaneous tissue
• Also called “hypodermis”
• We have adipose tissue (fat) in this area
STOP!
• Integumentary system coloring sheet
ANSWER THESE QUESTIONS ON THE
BACK OF YOUR COLORING SHEET
(QUESTION AND ANSWER):
1. The dermis is made out of what kind of tissue?
2. Where does the stratum basale get its nutrients
from? BE SPECIFIC!
3. Create a venn diagram detailing the differences
between the two types of sweat glands.
4. State the function of the arrector pili muscle.
5. Give 2 ways the body is involved in disease
prevention.
BURNS
• Types
• Thermal: contact with flame, heat, or scalding liquids
• Chemical: contact with acids, bases, and other chemicals
• Radiation: exposure to radiant energy from sunlight, x-rays,
or radiation from cancer treatments
• Electrical: electricity or lightning
BURNS
• Problems
• Body loses supply of nutrients that seep from burned areas
• Dehydration and nutrient imbalance can lead to circulatory
shock
• Not enough fluids in the system
• Susceptible to infection because of open wounds
ACID BURNING IN THE MIDDLE
EAST
• http://www.dailymotion.com/video/xx0to6_silentveil-a-documentary-by-depilexsmileagain_shortfilms
SEVERITY OF BURNS
• 1st degree:
• Epidermis is damaged and the area may be red and
swollen
• Can heal within a matter of days
• sunburn
SEVERITY OF BURNS
• 2nd degree burns
• Injury to epidermis and upper region of dermis
• Skin is red, painful, and blisters appear
• Usually no scarring
• 1st and 2nd degree burns = partial-thickness burns
SEVERITY OF BURNS
• 3rd degree burns
•
•
•
•
•
Destroy the entire thickness of the skin
Full-thickness burn
burned area appears blanched (white/gray) or blackened
Nerve endings are destroyed so there is no pain
Regeneration is not possible
• Skin grafting
BURN TREATMENT
• For minor burns (1st and 2nd degree)
• Cool the burn under cool running water
• Do NOT use ice
• Cover it with a sterile bandage
• Do not use butter or ointments if the skin is broken (can cause infection)
• Take over-the-counter pain reliever
• For major burns
•
•
•
•
Do not remove burned clothing
Do not immerse in cold water
Elevate burned body parts
Cover the area with cool, moist, sterile bandage
SKIN GRAFTING
BURNS
• Volume of blood can be
estimated by determining
how much area of the body
is burned
• Rule of 9’s
• Body is split up into 11 areas
(the torso/abdomen area are
usually combined), each
accounting for 9% of the total
body areas, plus 1% represents
genital area
Total:
100%
ADULT VS. CHILD PROPORTIONS
• Children have different body proportions than
adults
STOP!
• Calculating percent burn with Jack (Jr./Sr.) and Jill
(Jr./Sr.)
1) State location of burn (hello, body regions!)
2) State severity (partial/full thickness, as well as if it is 1st,
2nd, 3rd degree)
3) State if grafting must occur
4) Calculate the percent burn
• Get with another person, read them your report and see
if you both get the same burn percentage
SKIN CANCER GRAPHIC
ORGANIZER
• With your group members, develop a graphic organizer that
shows the 3 types of skin cancers featured in your text, as well
as integrating the ABCD rule
• MUST include:
•
•
•
•
The relative prevalence (most common, least common)
The cells affected (which layer, if there is a specific cell type)
Cure rate
How it is detected (what gives you the warning signs?)
• ABCD rule (goes with melanoma)
• Therapy (if mentioned)
• You will be presenting this information and drawing this
information on the board, explaining your organizer
• Again, multiple ways of presenting the information = multiple
opportunities for you to find out what makes sense to you