Transcript File - Mr. Haan`s Science

INTEGUMENTARY SYSTEM
Chp 5 pg 69
A. INTRO
1.
Skin
2.
Weighs 9 – 11 lbs
3.
7% of total body weight
4.
Ave person loses 40 lbs in a life time
5.
1.2 – 2.2 m2
B. 2 DISTINCT REGIONS
1. Epidermis
a. Made of epithelial cells
b. Protection
c. Dandruff – stratum corneum
2. Dermis
a. Bulk of the skin
b. Tough
c. Fibrous connective tissue
d. Vascularized
C. HYPODERMIS (SUBCUTANEOUS TISSUE)
1.
Below the dermis
2.
Not part of the skin – same protective
characteristics
3.
Functions
a.
Stores fat (adipose tissue)
b.
Anchors skin to mostly muscles – can still slide
c.
Shock absorber
d.
Insulator
THE SKIN
e. Thickens with weight gain
1) Women – thighs and breast
2) Men – anterior abdomen
D. EPIDERMIS
Cells of the epidermis
1.
a.
Keratinocytes
1)
Produces keratin
2)
Used for protection
3)
Produce rapidly
- calluses
b. Melanocytes
1) Produce melanin
2) Protection
c. Lagerhan’s cells
1) Phagocytes
2) Activate immune system
MELANIN VS NO MELANIN
d. Merkel Cells
1) Epidermal – dermal junction
2) Sensory receptor for touch
2. Layers of epidermis
a. Thick skin – Stratum corneum
1) Palms
2) Fingertips
3) Soles of feet
4) Help with “waterproofing”
b. Thin skin – Stratum basale
1) Rapid cell division
2) Langerhans and melanocyte cells
E. DERMIS
1.
Hair follicles, oil and sweat glands found here
2.
2 layers
a.
Papillary layer
1)
Made of collagen and elastin
2)
Vascular
b. Reticular layer
1) Deeper
2) 80% of thickness
3) Flexure lines
a) Dermal folds tightly secured to deeper
structures
b) Palms, soles, fingerprints
c) Skin doesn’t slide as well
Cleavage lines found here.
Invisible on outside. If cut
parallel to them skin heals
faster. Why is this
important?
F. SKIN COLOR
Due to 3 pigments
1.
a.
Melanin
1)
Brown to black
2)
Only pigment made in skin
3)
Freckles and moles
4) More sunlight – more melanin
a) Protects DNA from UV light
b) Absorbs light and dissipates it as heat
b. Carotene
1) Yellow to orange
2) Found in plants
3) Carotenaemia – turn orange from too much
MAGIC SCHOOL BUS – CAROTENAEMIA
http://www.youtube.com/watch?NR=1&v=_mHlf17f0Y0
c. Hemoglobin
1) Pinkish color from oxygenated hemoglobin
2) Caucasian skin contains little melanin so
epidermis is nearly transparent
G. APPENDAGES OF SKIN
1.
Maintain body homeostasis
2.
Sweat Glands
a.
Eccrine
1)
99% water
2)
Some salt and vit. C
3)
Acidic (4-6pH)
4) Heat induced sweating
- Starts at forehead then spreads
b. Apocrine
1) Ducts empty into hair follicles
2) Contain fatty substances and proteins
3) Yellowish color and odorless
4) Begin at puberty
5) Found in anal region, armpits, and groin
6) Sex attractant
7) Emotional induced sweating
a) Upset, scared, having pain
b) Starts at palms, soles, and
armpits, then spreads
c. Ceruminous gland – produce earwax
3. Sebaceous glands
a. Oil gland in hair follicle
b. Sebum – secretion to lubricate and waterproof
hair and skin
c. Acne – blocked gland w/bacteria and pus
4. Mammary glands
a. Located in breast tissue
b. Stimulated to produce milk by/after childbirth by
hormone from uterus
5. Hair
a. Found almost everywhere except…
Soles, palms, lips, nipples, portions of external
reproductive organs
b. Formed by cells of epidermis extending into
dermis
c. Follicle – forms hair shaft
1) Root – receives nutrients and grows
2) Shaft – keratinizes and dies
d. Arrector pili – muscle to cause hair to stand up
e. Alopecia – hair loss
https://www.youtube.com/watch?v=lc2f5gbCW0o
6. Nails
a. Keratinized cells growing out epithelial cells
b. Nail root
c. Lunula – half moon shaped germinal area
d. Strengthen and protect ends of digits
H. SKIN DISORDERS
1.
Warts – viral infection causing lump of skin
2.
Athlete’s foot
a.
Fungal infection on feet and toes
b.
Keep feet clean and dry to cure
3. Impetigo
a. Contagious bacterial infection with crusted
pustules
b. Common in kids
c. Caused by staph bacteria
d. Treated with antibiotics
4. Psoriasis
a. Chronic condition, red patchy skin w/silvery flaky
scales
b. Often along hairline
c. Treat with ointment
5. Eczema
a. Inflammation caused by sensitivity to some
chemicals
b. Usually very itchy
c. Treatment by avoiding causative agent
6. Dandruff
a. Excessive keratinization of scalp
b. Treated with anti-dandruff shampoo
7. Urticaria (hives)
a. Allergic reaction w/red bumps and itching
b. Helped with anti-histamines
Dandruff
SKIN DISORDERS
Hives
8. Leprosy (Hansen’s disease)
a. Bacteria eating away flesh of body
b. Caused by Mycobacterium leprae
c. Rare and very treatable
9. Cancer – melanoma or non-melanoma
a. Basal cell – most common & caused from UV
exposure
1) Red patch, smooth, round, raised edge
2) Most commonly found on forehead, tops of
ears and nose, cheeks
SKIN DISORDERS
Basal Cell
b. Squamous cell
1) Less common, same signs
2) May resemble a wart that
bleeds and scabs
3) Raspberry like
c. Melanoma
1) Unusual mole, spilled ink spot, black irregular
edges
2) Can be fatal if not treated
10. Wounds – cuts or punctures which bleed
a. Enzymes from cut tissue and platelets stimulate
clotting
b. Fibroblasts – promote growth of new tissue
c. Collagen fibers – give strength to healing process
and cause scar
STAB WOUND (KNIFE)
LACERATION ON RIGHT THIGH
DEEP LACERATION ON ARM/LEG
STAB TO HEAD
GUNSHOT TO ARM
I. BURNS
First degree
1.
a.
Only epidermis is
damaged
b.
Couple days to heal
c.
No special attention
needed
d.
Sunburn - usually
2. Second degree
a. Injure epidermis and upper
dermis
b. Blisters
c. Skin heals with little/no scarring
if properly taken care of
3. Third degree
a. Entire thickness of skin
b. Area appears gray-white,
cherry red, or blackened
c. Infection and fluid loss is
common
3RD DEGREE
4. 4th degree
a. Burned tissue down t bone
b. Limited survivability, often fatal
c. Cause fluid loss, heat loss, and infection
d. Isolation and skin grafting required for bad burns
J. Aging
1. Dermis thins
2. Fat tissue decreases
3. Collagen breaks down causing wrinkles
4. Elasticity decreases, fewer blood vessels, follicles,
sebaceous glands and sweat glands
Young
AGING
Old
K. Function and Homeostasis
1. Protection – mechanical
2. Water loss prevention
3. Vitamin D production
4. Sensory reception
5. Temperature regulation
a. Perspiration
b. Heat exhaustion – profuse sweating, red face,
need to cool down
c. Heat stroke – high temperature, no sweating, life
threatening, death follows soon
d. Hypothermia
1) Temperature below 98.6 F
2) Shivering, incoherent speech, loss of coordination
3) Further cooling…pulse slows, hallucinations,
unconsciousness, death
L. SAD (Seasonal affective disorder)
1. Depression like symptoms during seasons with little
or no exposure to sunlight
2. Need sunlight or artificial sunlight
M. This Bites
1. Bee sting
a. Inflammation
b. Pain
c. Swelling
2. Spider Bites
Garden Spider
Brown
Recluse
3. Centipede – rare but slightly poisonous
4. Snake: Copperhead
a. Redness
b. Swelling
c. Pain
Swelling
Poison Movement