Lec 2-6 (1) Flashcards
study of skin
Dermatology
Describe variations in the epidermis between different body regions
thick/thin skin
Describe variations in the epidermis between individuals
color, flushing, tan lines
Describe variations in the epidermis in thickness, color, skin markings
calluses, oiliness, birth marks
works as a pigment in the skin (flushing), an oxygen binding compound present in red blood cells, turns bright red upon binding oxygen
Hemoglobin
skin pigment, yellowish-brown produced and stored by melanocytes, transferred to other cells, protects skin from UV radiation ie skin cancer
Melanin
cells that produce and store melanin
Melanocytes
Same surface area of skin has ______________ melanocytes regardless of skin color
same number of
darker skin produces __________ colored melanin
more and darker
yellowish-orange pigment acquired from yellow-orange vegetables
Carotene
Which pigment accumulates inside subcutaneous fat and keratinocytes of stratum corneum, converted to vitamin A within body, plays important roles in vision, reducing free radicals, in immune function
Carotene
a mole, harmless overgrowth of melanin forming cells
Nevus
yellowish or brown spots on the skin, concentration of melanin or carotene
Freckles
skin discoloration due to benign blood vessel tumor
Hemangioma
type of hemangioma present at birth, known as strawberry-colored birthmarks
Capillary hemangiomas
type of hemangioma known as port-wine stains, involve larger dermal blood vessels
Cavernous hemangiomas
attachment points of collagen fibers on the skin
Cleavage lines
Which cuts related to cleavage lines scar more?
Cut parallel to a cleavage line heals cleaner; Cut across cleavage lines has more scarring
blood vessel diameter narrowed, shunted from periphery to internal organs
Vasoconstriction
Function of nails
protection and scratching
Function of hair
protection, signaling, insulation
nails, hair, exocrine glands derived from epidermal epithelium, formed from portions of epidermis invaginated into the dermis
Epidermal derivatives
Three types of hair
lanugo, vellus, terminal
fine, downy baby hair, appears in last trimester
Lanugo
primary human hair, on upper and lower limbs
Vellus
coarser, pigmented hair, on scalp, eyebrows, eyelashes, men’s beards, during puberty replaces vellus hair in axillary and pubic regions
Terminal hair
What makes hair grow faster
nutrition and calorie intake
Two types of sweat glands
merocrine and apocrine
Two types of perspiration from merocrine glands
sensible and insensible
drippy sweat, beads and rolls off
Sensible perspiration
sweat that evaporates straight out of the skin
Insensible perspiration
Glands that have a milky, smelly sweat, found in axillae, pubic, and nipple regions
apocrine glands
oily discharge produced by sebaceous glands through holocrine secretion
Sebum
Glands that discharge sebum
Sebaceous glands
modified apocrine sweat glands located in ear
Ceruminous glands
earwax, lubricates ear, anti-microbial properties
Cerumen
modified apocrine sweat glands of the breast, only in females, produce milk
Mammary glands
vitamin synthesized in skin, requires UV exposure and cholesterol in skin to synthesize
Vitamin D3
another name for Vitamin D3
Cholecalciferol
active form of vitamin D3, helps calcium absorption in body, synthesized in kidneys
Calcitriol
ability of skin to allow absorption of some substances and not others
Selectively permeable
describes ability of oil soluble drugs to be administered through skin
Transdermal administration
immune based cells in the epidermis
Dendritic cells
What does thick skin not have that thin skin does?
Thick skin does not have hair or sebaceous glands
replacing the same skin cells, restores organ function
Regeneration
replacement of skin cells with scar tissues, composed primarily of collagen, typically function is not restored
Fibrosis
Steps of wound healing
Wound happens and you bleed
Blood clot forms called scab
Regeneration and fibrosis from deep to superficial
Scar tissue is replaced by functional tissue and scab falls off
overproduction of scar tissue that may appear to be a tumor, possible side effect of surgery
Keloid
autoimmune disease that causes a rapid overgrowth of skin cells, can be painful
Psoriasis
body attacks itself
Autoimmune
UV exposure, corticosteroids, immunosuppressant drugs
Psoriasis treatments
burns that damage epidermis, slight redness and pain
First degree burns
burns that damage epidermis and dermis, causes blistering
Second degree burns
burns that damage epidermis, dermis, and subcutaneous layer, require hospitalization and cause bad scarring
Third degree burns
regions of the body are divided into multiples of 9% to quickly estimate amount of body burned. 99% means all but groin burned. 100% means all including groin burned. Babies are different rules.
Rule of nines
What happens when skin ages
cells get smaller, fewer, don’t work as well, don’t replace as well, and die
most common type of skin cancer that is the least deadly
Basal cell carcinoma
skin cancer of medium commonality, medium deadliness
Squamous cell carcinoma
least common skin cancer, most deadly skin cancer
Malignant melanoma
To be turned inside out or folded back on itself to form a cavity or pouch
invaginated
One popular treatment for wrinkles caused by repeated facial muscle expression is botulinum toxin type A
Botox
How does botox work
temporarily blocks nerve impulses to the facial expression muscles, thereby decreasing or eliminating the wrinkles they produce.
