chapter 5 - integumentary system Flashcards
your body system that includes your skin, hair, nails, and glands
integumentary
a skin doctor
dermatologist
the most superficial region of the skin
epidermis
of what tissue is the epidermis composed
keratinized stratified squamous epithelium
the waterproof protein in your epidermis
keratin
the most numerous cells in the epidermis
keratinocytes
the pigment-producing cells in the epidermis
melanocytes
the brown/black pigment produced by your skin in the presence of sunlight
melanin
cancer of the melanin producing cells
melanoma
What makes melanoma so dangerous?
metastasizes, resistant to chemotherapy
the region of skin beneath the epidermis, the true skin
dermis
Of what tissue is the dermis composed?
dense irregular CT
What is the purpose of the dermis having irregular CT?
can withstand stress from multiple directions
What is the region of skin beneath the dermis (3 terms)?
hypodermis, superficial fascia, subcutaneous
Of what tissue is the hypodermis mostly composed?
loose CT - adipose
What is the importance of the adipose in the hypodermis? Give three.
insulates, cushions and protects, and stores energy
What is the difference between thick and thin skin, and where is each found?
thick - 5 layers - palms and soles
thin - 4 layers - everywhere except palms and soles
Name the 5 layers of epidermis from superficial to deep, and give a short description of each layer.
stratum corneum - thick, dead, flattened cells (keratinized)
strtum lucidum - clear layer in palms and soles
stratum granulosum - grainy layer filling with keratin
stratum spinosum - prickle layer (cells are shrinking)
stratum basale - a single germinating layer
the immune cells of the epidermis - 2 terms
Langerhans cells - epidermal dendritic cells
What happens to the immune cells of the epidermis with age, and what is the result?
decrease in number - increased skin problems
Name, and describe the two layers of the dermis.
- papillary layer - consists of dermal papilla that interlock with the epidermis and create skin patterns
- reticular layer - lots of collagen fibers
What is the purpose of the friction ridges created by the pattern of dermal papillae in the reticular dermis?
grasping
What determines the pattern of friction ridges?
genetics
The overall pattern of collagen fibers in the dermis creates what?
lines of cleavage or tension lines
Who cares about lines of cleavage or tension lines, and why?
cosmetic surgeons because cutting with the pattern reduces scars
What is the importance of the abundant collagen fibers in the dermis? Give 2 answers.
- strength
2. binds to water and keeps skin hydrated
dermal folds near joints where the dermis is attached to deeper structures
flexure lines
torn collagen fibers in the skin (2 terms)
stretch marks or striae
What is the importance of the elastic fibers in the dermis?
help skin stretch and recoil
a separation of the epidermis and dermis where fluid accumulates between the layers
blister
Where on Earth does darker skin originate, and why?
equatorial regions - protects nuclei from sun damage
a yellow orange pigment in some plants
carotene
Where in the body does carotene tend to concentrate (2 places)?
stratum corneum
adipose
What vitamin is made from carotene, and what does it do for us?
vitamin A - essential for vision and epidermal health
Give a vegetable that contains carotene.
carrots
the iron-containing pigment in our blood that gives us a pink color
hemoglobin
when people appear blue due to a lack of oxygen in blood
cyanosis
when people appear red due to dilation of capillaries
erythema
What might make a person cyanotic?
heart and respiratory problems
turning white due to a lack of blood flow from fear, anger, or emotional stress (2 terms)
pallor or blanching
when people turn yellow due to liver issues
jaundice
when people turn a bronze color without excess sunlight (2 reasons)
- Addison’s disease
2. pituitary tumor
black and blue marks or bruises under the skin
hematomas
3 major skin appendages
hair, nails, glands
another name for a sweat gland
sudoriferous glands
the two main types of sweat glands
- merocrine or eccrine
2. apocrine
Which type of sweat gland is more numerous?
merocrine
What is sweat mostly made up of?
99% water
What is the main function of sweat?
evaporative cooling
Other than cooling, what are two major functions of sweat?
kills germs and excretes wastes (dilute urine)
What are the 2 main locations for apocrine sweat glands?
- axillary region
2. anogenital region
What causes apocrine sweat to stink?
It is more nutritious so bacteria feed on it, and the bacteria stink.
When do apocrine glands really start functioning?
puberty
What are ceruminous glands, and where are they found?
wax glands in ear
What is the importance of cerumen or earwax?
prevent stuff from entering ear
What are mammary glands?
breast milk producing glands
oil glands
sebaceous
What type of secretion is oil?
holocrine
What is the importance of oil to the skin?
keep it moisturized so it doesn’t crack and let germs in
When do sebaceous glands really start functioning?
puberty
What are sebaceous glands usually attached to?
hair follicle
Other than moisturizing, what does sebum do for you?
kills germs
The contraction of what muscle helps to expel the sebum from the hair follicle?
arrector pili
at puberty, when oil glands get blocked and accumulate sebum
whiteheads
oxidized whiteheads
blackheads
inflammation of sebaceous glands accompanied by bacterial infection and pimples
acne
cradle cap - overactive sebaceous glands in infants
seborrhea
the structure that produces the hair
hair follicle
a hair
pilus (pili)
functions of hair
protect from insects, protect from heat loss, protect from sunlight, protect from abrasion and trauma, shield eyes, filter air we breathe
Of what chemical are hair and nails composed
keratin
Name the three layers of a hair shaft from outside to inside.
cuticle, cortex, medulla
What is the term for damaged hair cuticle?
split ends
the nerve endings that wrap around the bottom of a hair follicle
root hair plexus, hair follicle receptor,
the two layers of the hair follicle
internal root sheath (epidermis) and external root sheath (dermis)
the actively growing part of the hair
matrix
What do the arrector pili muscles do to warm a person up?
Goosebumps are tiny muscles contracting. They also trap air next to the body.
What is the difference between vellus and terminal hair?
vellus - peach fuzz
terminal - more coarse and dark (after puberty)
Why are the hairs on your scalp longer than eyebrows?
longer growth cycle between rest cycles
What do we call a hair that is ready to fall out?
club hair
How many hairs can a person lose a day without being sick?
around 100
What are some factors that can increase hair loss?
stress, poor nutrition, heavy metal poisoning, fever, certain drugs
excessive hairiness, often adrenal gland or ovarian tumors cause it
hirsutism
hair loss
alopecia
autoimmune hair loss in patches
alopecia areata
low pH of skin makes it be called what
acid mantle
What does our skin protect us from?
abrasion, dehydration, infection
What does our skin make in the presence of sunlight?
melanin and vitamin D
What is the importance of vitamin D?
allows us to absorb calcium
What is the importance of melanin?
shades our nuclei from sun damage
specialized nerve endings for pressure
Pacinian corpuscles
specialized nerve endings for touch
Meissner’s corpuscles
What do free nerve endings detect?
pain and temperature
Name, and describe the three major types of skin cancer.
melanoma - dark tumor of melanocytes
squamous cell carcinoma - often an open sore, upper cells of skin
basal cell carcinoma - often raised and shiny, lower cells of epidermis
What is the rule for telling if a growth is cancer?
ABCDE Rule A is for asymmetry B is for border C is for color D is for diameter E is for elevation
What are the 2 major threats to life after a serious burn?
- sepsis - widespread bacterial infection
2. dehydration
How do doctors estimate the extent of burn damage?
rule of nines
Name and describe the 3 major categories of burns.
1st degree - epidermis only - red, swollen, and painful
2nd degree - epidermis and dermis - will blister
3rd degree - epidermis and all of dermis - no pain or swelling
Why don’t third degree burns hurt or swell?
no blood vessels or nerve endings left
How must 3rd degree burns be treated?
IV fluids, antibiotics and calories
grafting to cover wound
debridement to prevent infection and fluid loss as well as lessen scars
downy coat of hair on a newborn
lanugo coat
the waxy coating of a newborn made by sebaceous glands
vernix caseosa
white spots that are collections of keratin in newborns
milia
What happens to the skin at puberty
glands increase activity - acne
What happens to the skin around 30?
cumulative sun damage starts to show
inflammation of skin
dermatitis
