Transcript Integumentary System

OCTOBER 2, 2013
STANDARD: SAP2a Relate the structure of the
integumentary system to its functional role in
protecting the body and maintaining
homeostasis.
EQ: How does the integumentary system
protect the body?
Warm-Up: Complete ARG 46.4 (on your desk).
Write the answers only in your composition
book.
What if you were shopping for
a coat and you were told by
the sales person it’s
waterproof, stretchable,
washable, permanent-press,
repairs small cuts, rips and
burns, and is guaranteed to
last a life-time with reasonable
care, would you buy it?
http://app.discoveryeducation.com/
search?Ntt=tattoos+skin
SKIN, GLANDS, HAIR, & NAILS
Skin – vital to homeostasis
• Functions:
1. Protective covering
2. Aids in regulation of body
temperature
3. Retards the loss of water from
the body
OCTOBER 4, 2013
EQ: What is the structure of the integument?
WARM-UP:
RIDDLES!!! COPY & SOLVE
1. What two things can you never eat for breakfast?
Lunch and Dinner
2. While on my way to St. Ives, I saw a man with 7 wives.
Each wife had 7 sacks. Each sack had 7 cats. Each cat
had 7 kittens. Kittens, cats, sacks, wives. How many were
going to St. Ives?
Just one -the man
3. I can be found where anything cannot, dead men eat me
all the time, but if a living man eats me, he will die. What
am I?
Nothing
Layers of Skin
1. Epidermis
Stratified squamous epithelium
– Surface of the skin
– No blood supply
a. Stratum basale- constantly dividing,
well nourished
b. Stratum spinosum-flatter & keratinize
& die
c. Stratum granulosum-same as
(spinosum)
d. Stratum lucidum-only found in skin
that is hairless
e. Stratum corneum-20-30 cell layers
thick, ¾ of epidermal thickness
2. Dermis- your “hide”-ex. belts, bags,& shoes
• The dermis binds the epidermis to underlying
tissues.
• The dermis contains connective tissue, blood
vessels, nerve fibers, hair follicles, sweat glands
and sebaceous glands.
• These blood vessels are important to the
process of thermoregulation.
• 3. Hypodermis- below the dermis; adipose
tissue (shock absorber)- responsible for
curves
• Subcutaneous layer (hypodermis)– found
beneath the dermis; contains CT and adipose
tissue (fat) to insulate the body.
CELLULAR MATURITY:
1. As cells mature, they undergo
keratinization (cytoplasm develops
strands of keratin to harden cells).
2. As cells move toward the surface, they
lose their nutrient supply (blood).
3. These cells eventually die and are
quickly replaced.
Melanin: yellow-brown
• Dark pigment found in
the stratum basale;
produced by
melanocytes.
• Pigment absorbs light
energy, protecting
deeper cells from
damaging effects of
sunlight.
• Melanocytes have
long, pigmentcontaining extensions
that pass between
epidermal cells –
extensions can
transfer melanin to
upper level of
epidermal cells
(suntan).
Several factors influence the color of a
person’s skin:
• People whose genes code for a large
amount of melanin have darker skin.
• Environmental factors – sunlight
stimulates additional pigment to be
produced.
• The amount of oxygen in the blood in the
dermal vessels (pink or blue tint to skin).
• Emotional stimuli- blush=red, pale=white,
jaundice=yellow, bruise=black & blue
SKIN STRUCTURE QUIZ
1-2.Name 2 functions of skin?
Protection
Fluid retention and excretion
Vitamin D production
Houses nerve receptors for pain and temperature
3. Which layer is composed of adipose tissue?
Hypodermis/subcutaneous tissue
4. Which of the 5 zones of the epidermis is closest to the dermis?
Stratum Basale
5-6. Name 2 things found in the dermis?
blood vessels, CT, nerve fibers, hair follicles, sweat
glands & sebaceous glands
7. What is the thickest layer of skin?
Dermis
OCTOBER 8, 2013
EQ: How do accessory organs help in maintaining
homeostasis?
Identify the parts of the skin:
1
2
3
1.Take out two sheets of paper and
number one of them from (1-10) (you
need the other one later)
2. Head it “Skin Structure Quiz”
3. Put your technology in your bag or
purse.
4. Take everything else off of your desk.
Decubitus Ulcers
• Also known as
bedsores.
• Pressure results in
interruption of blood
flow to an area of the
skin.
• The tissue in that
area dies.
Accessory Organs of the Skin
EXOCRINE GLANDS
1. Sebaceous glands-”seb” (grease)
• Produce sebum (a mixture of fat and cellular
debris), keeps skin soft and waterproof.
• Sebaceous glands- can be overactive due to
hormonal changes during puberty
• Excessive secretions cause the openings of hair
follicles to become dilated and plugged, causing
blackheads.
• What causes pimples/acne?
• presence of pus-forming bacteria
2. Sweat glands-sudoriferous (sudorsweat)
2 types :
eccrine-found all over the body
secrete: water, salts, Vit. C, urea,
uric acid, & lactic acid
apocrine- found in axillary & genitals
(larger)
secrete: fatty acids & proteins +
secretions of eccrine gland
*activated by pain, stress, sexual
foreplay
NAILS
*Protect the ends of fingers and toes.
*Stratified squamous epithelium with
much keratin.
Hair follicles
• A hair develops from a group of epidermal cells
at the base of the hair follicle.
• A hair is composed of dead epidermal cells that
are pushed toward the surface.
• Arrector pili muscle – attached to hair follicle.
When this muscle contracts, the hair stands on
end (cold or upset).
HAIR
1. Hair color – abundance of melanin
(dark hair), some melanin (blonde hair).
2. Shapes of hair shaft:
*Oval- produces wavy, silky hair
*Flat, ribbonlike- produces curly, kinky
hair
*Round- produces straight, coarse hair
Thermoregulation
1. Excessive heat – Hyperthermia
•
Hypothalamus signals blood vessels to dilate; more
heat carrying blood reaches the dermis – heat escapes
to the outside.
•
Eccrine glands release water onto surface of the skin –
the water evaporates, carrying heat with it.
•
Heart rate increases – blood is moved from deeper
tissues to the skin.
•
Breathing rate increases – heat is lost from lungs as air
is moved in and out.
2. Hypothermia - lowered body temperature
*Dermal blood vessels contract; this reduces heat loss.
*Shivering – muscle contractions create body heat.
*Heart rate decreases – blood is moved from surface to
deep tissues.
*Breathing rate decreases – to minimize heat lost.
Face Transplant
OCTOBER 16, 2013
SAP2a
EQ: How do skin cancers affect the bodies ability to
maintain homeostasis?
WARM-UP: (Write questions and answers)
1. What are the two major life-threatening concerns
when a person has 3rd degree burns?
2. What do we call burns that only affect the
epidermis and the upper part of the dermis?
3. What happens 24hrs after a third degree burn?
Skin Cancers
I. Basal Cell Carcinoma
•
•
•
•
•
Least malignant cancer, most common (30%
of all caucasians get one in their lifetime).
Originate in stratum basale of epidermis.
Fully cured by surgery in 99% of cases.
Result from effect of sunlight on DNA of
epithelial cells.
Closely related to regular sun exposure.
II. Squamous cell carcinoma
1. Arises from cells of stratum spinosum
2. Grows faster, more likely to
metastasize (spread).
3. Found on scalp, ears, lower lip,
hands-scaly reddened elevation.
4. Sun-induced
5. If caught early, prognosis is good.
III.
Malignant Melanoma
1. Originate in melanocytes; pigmented
lesions
2. Begins as a spreading brown or black
patch
3. Rapid metastasis to surrounding lymph
and blood vessels
4. Irregular margins
5. Related to short, intensive exposure to sunlight
6. 1/3 develop from pre-existing moles
ABCDE rule for skin cancers
A = assymetry
B = border irregularity (indentions)
C = color (several colors, blues, reds)
D = diameter (larger than 6 mm)
E = elevation above surface of the skin
OCTOBER 16, 2012
WARM-UP:
Standard: SAP2a
EQ: How can burns effect homeostasis in the
human body?
Complete Review Questions pg 131 (11-14),
answers only (I’ll be coming around to check
for completion before we go over it)
Burns
• Tissue damage caused by intense heat,
causing cell death.
• Immediate threat to survival – catastrophic loss
of body fluids from burned surfaces leading to
dehydration.
• This imbalance can lead to renal (kidneys)
shutdown and shock.
• Burn patients need thousands of extra calories
to replace lost proteins and allow tissue repair.
• Infection is the leading cause of death in burn
victims.
1. Burned skin is sterile for 24 hours, then
bacteria and fungi invade areas where
skin barrier is destroyed.
2. Bacteria and fungi are nourished by the
dead tissue and protein-rich fluid lost from
burned surfaces.
Categories of Burns
First degree burns
1. Only epidermis is damaged
2. Symptoms: redness, swelling, pain
3. Heals in 2-3 days without attention
*Example: sunburn
Second degree burns (1st and 2nd are
called partial-thickness burns)
1. Epidermis plus upper region of dermis is
damaged
2. Redness plus blisters
3. Skin regeneration within 3-4 weeks
Third degree burns (full-thickness burns)
1. Burned area is gray, red, or blackened
2. No pain at first – nerve endings are destroyed
3. Because of fluid loss, patient can’t wait for
epithelial regeneration; skin graft is necessary.
4. Dead skin is removed; area is flooded with
antibiotics and covered with synthetic skin,
cadaver skin, or amniotic sac.
5. Autograft – healthy skin is transplanted from
one area of patient to damaged area.