Integumentary system Flashcards
what is the difference between thick and thin skin.
Thick skin has 5 layers of epidermis (stratum lucidum)
Thin skin has hair, sweat and sebaceous glands, Thick skin has only sweat glands.
Functions of the skin (6)
- Resistance, protection
- Waterproofing and UV
- Vit D and calcitriol
- Sensation
- Thermoregulation
- Nonverbal communication
Name cells that are found in epidermis (5) and what layer they are in
Stem cells (deepest layer) Keratinocytes Melanocytes (DNA + pigment) basal layer Tactile (Merkel) cells (basal layer) Dendritic (Langerhans) (spinosum and granulosum)
What 2 substances form in stratum granulosum
Lamellar granules (glycolipid secretion -waterproofing) keratohyalin granules
Name 4 +1 layers of epidermis
Basale (germinotium) spinosum granulosum (lucidum) corneum
clear protein found in stratum lucidum
eleidin
two structures that make the border between epidermis and dermis wavy
dermal papillae and epidermal ridges
2 layers of dermis
papillary layer (thin, areolar, small blood vessels) Reticular layer (dense irregular, less ground substance, glands and hair follicles)
Stretch marks
Striae (torn collagen)
what does hypodermis consist of
areolar and adipose tissues, highly vascular
5 sensory receptors in skin
- Tactile corpuscles (Meissner’s)
- Pacinian corpuscles (lamellated)
- Tactile (Merkel) discs
- Free nerve endings
- Tactile discs
Meissner’s Tactile corpuscles (location and function)
papillary layer of dermis (esp sensitive in hairless spaces)
light touch, texture
Pacinian (lamellated) corpuscles (location and function)
down by subcutaneous (esp hands, feet, breasts, genitals)
deep pressure receptor, stretch, tickle, vibration
Merkel’s (tactile) discs
merkel cells + associated nerve ending = merkel discs
basal layer of epidermis
light touch, texture, shapes and edges
free nerve ending (location and function)
skin and mucous membranes
warm, cold and pain receptors (nociceptor)
Tactile discs (location and function)
around hair follicle
light touch, hair movement
what affects skin color (3) and where they are found
Melanin (mostly basale + spinosum)
Hemoglobin (near blood vessels - in dermis)
Carotene (stratum corneum and subcutaneous fat)
2 forms of pigments of melanin
eumelanin - brownish black
pheomelanin - reddish yellow (sulfur-containing)
Blue skin appearance
Cyanosis
Redness of skin
erythema
pale ashen skin color
pallor
lack of melanin
albinism
yellowing of skin and whites of the eyes
Jaundice
bruising
hematoma
golden-brown color
Bronzing (Addison disease) Hormon deficiency of adrenal glands.
Fingerprints
friction ridges
creases
flexion lines
Flat melanized patches
freckles
Elevated patch of melanized skin, often with hair
Mole
Birthmarks (3 kinds)
Skin discolored by benign tumors of the blood capillaries
- capillary hemangioma
- cavernous hemangioma
- port-wine stain
Pilus
hair
3 types of hair
- Lanugo (fetal)
- Vellus (kids and women)
- Terminal hair (men and scalp, brows, lashes, groin, axillary)
3 areas of hair along the length
shaft (above skin, dead)
root (inside the follicle, dead)
bulb (where hair originates, living)
part of vasculary connective tissue that is source of nutrition of hair
dermal papilla
hair growth center
hair matrix (mitotically active)
3 areas of hair from inside out
medulla (+air)
cortex (most of the bulk) pigment is here
cuticle
Follicle (location and 2 sheaths)
dermis and sometimes hypodermis
- epithelium root sheath
- connective tissue sheath
hair muscle
piloerector muscle
aka pilomotor muscle
aka arrector pili
3 stages of hair cycle
Anagen - growth (6-8 years), club hair might still be present
Catagen - degenerative stage (2-3 weeks), club hair is forming
Telogen - resting stage (1-3 month) papilla reaches the bulge
Thinning of the hair
alopecia (disease, stress, ragiation, aging)
excessive hairiness in areas that are not usually hairy
hirsutism
nail “cuticle”
eponychium
white area at the base of the nail
lunule
other name for sweat glands
sudoriferous
bad sweat odor
bromhidrosis
Apocrine sweat glands
- hormonal, (pheromones)
- larger ducts lumens that merocrine
- sweat is thicker and milkier (more fatty acids)
- usually associated with hair
Merocrine sweat glands
- under neurologic control (cool off, waste, -acidity)
- all over the body
- secrete into pores, not hair
2 types of merocrine perspiration
- insensible perspiration
- diaphoresis
Sebaceous glands (location, type of secretion)
associated with hair follicle
holocrine secretion
Glands if external ear canal
Ceruminous
cerumen - earwax
mammary glands
do not equal breasts
modified apocrine glands
rich secretion leads to nipple
Burned, dead tissue
ESCHAR
removal of toxins from eschar
debridement
partial thickness burns
1st and 2nd degree, epidermis and part of dermis
full thickness burns
3rh (4th if there is bone affected) + muscle
Calcitriol
Endocrine function hormones synthesized by keratinocytes.
Affects of:
skeletal - absorption of calcium
endocrine - hormone secretion depends on calcitriol
skin and immune system
dendritic cells alert immune system when pathogens breach the epidermal layer
