Skin ~BIO~
Terms
undefined, object
copy deck
- Skin
-
-made of keratin
-k = waterproof protein
-grows in layers
-repairs itself
-loose connective tissue = stretchy
-barrier, protects, keeps out bacteria, retains body fluid, regulates body temp, eliminates waste -
Skin
Epedermis -
-outer layer
-shed skin when it grows
-dead, flat skin cells
-hair follicles
-Basal Layer: bottom living layer (blood diffuses by osmosis thru blood vessels to basal)
-melanocysts in basal -
Skin
Dermis -
-inner layer
-live cells
-blood vessels, glands (sweat=cool, oil=smooth skin), sense nerves, muslce fibers (goose bumps)
-fat layer beneath it - Nails
-
-keratin, modified hairs, protein
-cells grow under skin at nail root around base/sides of nail plate
-3-6 months for complete growth (continuous)
-excersize = faster growth -
Nail
Parts -
Nail Matrix- area in which nail grows
Nail Plate- clear nail part
Nail Bed- holds nail in place w/skin (tissue + blood vessels)
Opinchium- cuticle -
Nail
Injury -
Hangnail- torn skin around nail
-due to dry skin/bite
Ingrown Nail- nail plate grows into nail bed
-due to tight shoes, genes
Leukonychia- (white spots) damaged matrix
-often = need more zinc - Hair
-
Hair follicle- cluster of cells in epedermis
1-cells grow at hair root (fed by tiny blood vessels)
2- pushes up shaft (visible hair)
3-cells die as they move up shaft away from blood vessels
4-become hard keratin
-scalp hair grows continuously
-others grow 2 years, fall out
-protect, insulate, regulate temp - Tanning
-
-melanocysts in epedermis basal layer release melanin
-melanin (pigment) protects body from sun rays
-skin = dark -
Tanning
Dangers -
1- Not enough melanin to prootect skin
2-Rays go to in skin
3-Sunburn (red, pain, inflammed, peeling)
4-Repeated Sunburn...
5-SKin Cancer:
-sun mess up DNA
-modifies cell genes
-replicate = tumor
-premature aging of skin - Tanning Prevention
-
-stay out of sun between 10-2
-wear protective layers
-SPF 30+
-reapply often
-waterproof
-don't wait for burn symptoms (takes 2-4 hours to show) - Coloration Skin + Hair
-
-hereditary
-melanocystes produce melanin (pigment)
Eumelanin (brown/black hair)
Pheomelanin (red)
Low Melanin (blond)
Melanocysts don't work (gray) - Moisturizers
-
-have water + oil
-water diffuses in epedermis skin cells thru ossmosis
-plumps them up
-oil keeps water from evaporating - Wrinkles
-
Young:
-have elastin + collagen in loose connective tissue
-skin retains water well
Old:
-skin loses elastin/collagen
-can't retain water well
-skin = thinner
Result:
-fat dissapears
-epedermis sags
Alpha-Hydroxy Cream-
-water diffuses in cells in folds in skin
-plumps them up
-oil holds it in - Sweat
-
-sweat glands in dermis/epedermis in hair follicle
-excretory organ = release excess water, urea, salts
-regulates body temp:
1-body temp increases
2-Stimulates glands in hair follicles to release sweat
3-water evaporates w/heat + skin is cooled -
Sweat
Yellow
BO -
BO:
-bacteria mixes w/sweat in hair follicle
-metabolizes protein
Yellow:
-sweat has carbs in it -
Sweat
Antiperspirants -
-clog/block pores w/astringents so they can't release sweat
-body can't cool
-deo neutralizes smell - Acne
-
-plugged pores
-gene triggers puberty, triggers hormones
1-increase in hormone level
2-oil glands more active
3-sebaceous follicle (S gland + hair follicle) make pore
4-oil secretions of sebum (fatty substance) build up underneath + plug it up
5-bacteria enters
WBC fight
=pimple -
Acne
Treatments -
-to prevent acne
-improve acne
-prevent scarring
-decrease sebum production, reduce bacteria, eliminate inflammation - Blisters
-
1. Skin rubs against something
2. Rubs off inner layer of skin but not outmost
3. Serum (fluid) enters from nearby tissues as result of damage - Calluses
-
1. area often rubbed, irritated, blistered
2. skin cells in are die often
3. dead cells accumulate + harden/thicken
4. protects against pressure,friction,injury