Chapter 5 Flashcards
most superficial layer of skin, avascular, made of epithelial tissue. consists of 5 layers
epidermis
most superficial layer of epidermis, 20-30 layers of dead squamous cells
stratum corneum
single layer of cells on top of the dermis, constantly divides and produces new cells.
stratum basale
second layer within skin, composed of dense irregular connective tissue.
dermis
Lies below dermis, not part of skin, contains loose CT and adipose, attaches skin to muscle and bone
hypodermis
underneath the skin
subcutaneous
special dendritic cells in stratum basale, phagocytize microbes
langerhan cells
produce melanin, responsible for skin colour
melanocytes
produce and store thick waterproof protein called keratin
keratinocytes
new cells with keratin, push old cells to surface. produce layer of hard dead cells.
keratinization
autoimmune disease, immune cells trigger epidermis to divide too quickly.
psoriasis
thickened area of stratum corneum, forms when exposed to frequent friction
callus
when stratum corneum thickens over bony prominence
corn
upper part of the dermis, projections, contain blood vessels, nerves, hair follicles
dermal papilae
Develop when there is constant pressure on single area of skin, blood supply to dermis is blocked
debcubitus ulcers
Types of injections
subcutaenous, intradermal, intramuscular, intraperitoneal, intravenous
absence of melanin due to genetics
Albinism
yellow-orange pigment, fat soluble, collects in lipids of stratum corneum
carotene
blue colour due to low oxygen or blockage of blood vessels
cyanosis
patches of depigmentation, melanocytes die or are unable to function
vitiligo
excessive hairiness in women
hirsutism
sweat glands, two subtypes, present in all regions of skin except nipples and parts of genitalia.
sudoriferous
numerous in palms and soles. sweat is mostly water, helps lower body temperature
eccrine sweat glands
inactive until puberty, contain sweat and secretion rich in organic substances. source of body odour
apocrine glands
associated with hair follicle, produce oil or sebum, lubricates skin, hair.
sebaceous glands
hair thinning and baldness
alpoecia
hair follicles attacked by immune system
alopecia areata
hormonal balding, male pattern baldness
androgenic alopecia
fast flowing sebum, overactive sebaceous glands
sebhorrea
most common type of skin cancer, cells in stratum basale affected, rarely metastasize and 95% easily cured
basal cell carcinoma
cells above stratum basale affected, sometimes metastasizes, kills 1% of cases, warts and scabs
squamous cell carcinoma
Arises from melanocytes in mole, very deadly unless caught early
maligant melanoma
form of skin cancer commonly found in people with weak immune systems
kaposi’s sarcoma
damage only epidermis, mild pain and erythema, no blisters. heals within 3-6 days
first degree burn
destroys epidermis and part of upper dermis, redness, pain, edema, blisters. epidermis seperates, 3-4 weeks
second degree burn
destroys epidermis and dermis, most skin functions lost. burned areas are marble white or charred
third degree burn
destroys tissues down to the bone, very unlikely to survive.
fourth degree burn
body temperature below normal, uncontrolled shivering, pulse slows
hypothermia
body temperature above normal, heat exhaustion and heat stroke
hyperthermia
cytokine, mediators of inflammation after injury
histamine
redness of skin
erythema
swelling of skin
edema
dried clot
scab
dead white blood cells, other cells, fluid
pus
