chapter 4 Flashcards
integumentary system
skin, hair, nails, sweat glands, oil glands, mammary glands (environmental protection, thermoregulation, synthesis and storage of lipid reserves, excretion, synthesis of vit d3, sensory information, immune response against pathogens and cancers in the skin)
cutaneous membrane
epidermis and dermis
accessory structures
hair follicles, exocrine glands, nails
epidermis
protects from trauma, chemicals, controls permeability and prevents water loss, prevents entry of pathogens, synthesize vitamins, detect pressure, pain, temp
dermis
papillary layer and reticular layer
papillary layer
nourishes and supports the epidermis (consists of dermal papillae, capillaries, nerve axons)
reticular layer
restricts spread of pathogens penetrating epidermis, stores lipid reserves, attaches skin to deeper tissue, sensory receptors detect touch, pressure, pain, vibration, temp, blood vessels assist in thermoregulation (consists of interlocking connective tissue made of collagen, hair follicles, sweat glands and sebaceous glands)
hair follicles
produce hairs that protect skull, produce hair that provide delicate touch all over the body(bulbisinthefolliucle)
dermis
hypodermis/ subcutaneous layer is the deep layer of the dermis (hypodermic injections and subcutaneous needles)
subcutaneous layer
contains half of the body’s fat, not technically considered part of the ingeument just helps to stabalize it
thick skin
found on palms and soles, made of five layers
thin skin
found on the rest of the body, made of four layers (eyelids are the thinnest skin)
four cell types of the epidermis
keratinocytes, melanocytes, Merkel cells, langerhans cells
keratinocytes
produces a tough protein called keratin (water resistant and abrasion resistant)
melanocytes
pigment cells located deep on the epidermis, produce melanin (skin color
langerhans cells
fixed macrophages
merkel cells
sensory cells
layers of the epidermic (deep to superficial)
stratum basale -> stratum spinosum -> stratum granulosum -> stratum lucidum (lightest layer) -> stratum corneum (dead skin layer filled with keratin)
stratum basale
attached to basal membrane, contains epidermal stem cells, melanocytes and merkel cells, active reproduction
stratum spinosum
has langerhans cells and melanocytes, keratinocytes are bound by desmosomes (like velcro)
stratum corneum
multiple layers of dead interlocking keratinocytes, kinds dry, water resistant but not waterproof, slow water loss
stratum granulosum
keratinocytes produce lots of keratin
epidermal ridges
stratum germinativum forms epidermal ridges, the ridges (dermal papillae) extend into the dermis, creates ridges we call fingerprints
basal lamina
basement membrane
dermal papilla
increases surface area for blood vessels, no blood flow on epidermis
skin color
due to dermal blood supply, thickness of stratum corneum, various concentrations of carotene (yellow and orange) and melanin
melanin pigment
pigment sits between the stratum basale and basal lamina (for darker skin)
keratinocytes tanning
tanning increases melanin going into keratinocyte
melanin
protects against skin cancer and mutations because it acts as an umbrella over diving cells
capillaries
feed the epidermic bc the epidermis does not have blood vessels
empty space in the papillary layer of the dermis
empty space for fluid/ macrophages and it cleans the area of germs
wrinkles
due to age, uv light, and smoking (can cause a vitamin c deficiency which means less collagen in the dermic which means the skin wont stretch and recoil as well)
stretch marks
stretching from prego causes reticular fibers to break, skin does not recoil
lines of cleavage
fibers have a tendency to organize in parallel fashion, they have a pattern all over the body, surgeons cut parallel to them to reduce scaring
subcutaneous
made of adipose tissue and major blood vessels
hair
made of keratin (skin and hair are dead) cuticle/ medulla is what sticks out (mena dn women have equal amounts of hair)
hair follicles
cells are layered in concentric rings
sebaceous gland
makes oil
arrector pili muscle
responsible for goosebumps from contracting, keeps you warm
hair bulb
the only part of the hair that is alive
capillary in hair
connect to hair papilla and nourishes the hair
medulla
core of the hair that contains soft flexible keratine
cortex
contains thick layers of hard keratin which give the hair its stiffness
cuticle
thin, rough, contains hard keratine
vellus hair
covers most of the body; women have more of it
intermediate hair
covers the arms and legs (men have more of it)
terminal
covers the head, eyebrows, lashes, pubic, axillary and continues to grow long)
functions of the hair
protection from sun (men= more ear cancer), insulation (warmer in winter cooler in summer), guard nose and ear entrances, hair movement sends impulses to the brain (bug crawling on arm), and contraction of arrector pili muscles
hair color
due to variation in melanin production by melanocytes, melanin production decreases with age (old=gray), 2 types one for blond/red and one for dark
sweat glands
apocrine glands, ceruminous glands, mammary glands, merocrine glands,
gland functions
lubricates the epidermis, excretes waster, assists in the thermoregulation
chemo
affects hair cells becuase they are fast reproducing cells, just like gut cells
endocrine
dumps hormones into blood stream
exocrine
dumps into ducts that go into/ out of the body (pancreases is both endo and exo)
sebaceous glandss
secrete sebum to lubricate the skin, found all over the body except for the palms and the soles, lots on forehead, face and upper back, if they get blocked acne may occur)
sebaceous follicle
emptys onto skin
sebaceous glands
empty onto hair
cells die
produce sebum
apocrine gland
scent underarm syncs periods, lots in armpit and nipples, odorous secretions (pheromones) baby also recognize small to feel safe w mom, bacteria is what creates b.o. smell not sweat, kids dont have under arm sweat glands (DO NOT REGULATE TEMP) `
merocrine glands
regulate temp, also called ecrine glads, found all over the body, lots on palms and soles, make sweat to cool (regulate temp)
mammary glands
type of apocrine gland; produce milk from hormones from pituitary gland (men can produce milk because of too much prolactin (tumor on pituitary))
ceruminous glands
water proofs ear, a type of apocrine gland, only in the ear canal, produce cerumen (wax), minimal protection
nails
protection for the tips of the fingers and toes; consists of free edge, lateral nail fold, lunula, eponychium (cuticle) and hyponychium)
nail root
only living part of the nail
nail component
made of dead keratinized nail
aging
epidermis become thinner, dermis becomes thinner, langerhans cells decrease (lower immunity), vitamin d synthesis declines, melanocyte decline, glandular activity decline, hair follicles stop working and skin does not repair as much
