Integumentary system Flashcards
2 components of the integumentary system
cutaneous membrane
accessory structures
cutaneous membrane structure
epidermis
dermis - papillary, reticular
hypodermis
what’s the organisation of the epidermis
stratified squamous epithelial cells
regeneration of the epidermis
basal keratinocytes divide
shrink and dehydrated
grains of keratin produced
dead flat clear cells form which lack organelle
cells shed
structure of epidermis
basement membrane
stratum basal
stratum spinosum
stratum granulosum
stratum lucidum
stratum corneum
surface
thick vs thin skin: location
thick - finger, palm, feet
thin - everywhere
thick vs thin skin: thickness
thick- 0.6-4.5mm
thin - 0.1-0.15
thick vs thin skin: strata
thick - thicker lucidum, spinosum and corneum
thin - no lucidum and thinner others
thick vs thin skin: ridges
thick - yes
thin - no
thick vs thin skin: hair follicles
thick - no
thin - yes
thick vs thin skin: sweat glands
thick - more
thin - less
thick vs thin skin: sensory receptors
thick - more
thin - less
role of melanocytes and keratinocytes
secrete melanin to protect from uv
skin pigments
carotene - yellow
melonin - brown
blood - pink
dermis structure
collagen and elastic fibre - support epidemris
papillary layer of areolar tissue
reticular layer - fibrous network
blood vessels - papillary plexus, cutaneous plexus
what type of tissue is the dermis
loose and dense connective tissue
hypodermis
underlayer
loose connective tissue (areolar and adipose)
superficial fasciae tissue type
areolar and adipose tissue
deep fascia
strong fibrous internal network
dense connective tissue
bound to tendons
subserous fascia
areolar tissue
role of hair follicle
protection
insulation
sensation
hair follicle structure
root hair plexus
hair root in connective tissue sheath
arrector pill muscle
subcutaneous gland
shaft
hair structure (working inwards)
connective sheath
glassy membrane
external root sheath
interbal root sheath
cuticle (thin hard keratin)
cortex (thick hard keratin)
medulla (soft keratin)
how fast does hair grow a day
0.33mm
sebaceous glands and follicle functions
secrete sebum
waterproofing
hair growth
end - follicle inactive, connection break = new growth
nail structure (from base)
eponychium (cuticle)
proximal nail fold
lunula
nail body
lateral nail fold
free edge
what cells are the nail
keratinised epithelial c ells
2 types of sweat gland
apocrine - smelly, thick discharge
merocrine - thinner watery discharge
function of sweat glands
cooling
excretion
protection
degrees of burn
1st - epidermis affected
2nd - some dermis
3rd - sensory nerves destroyed
injury repair stages
- bleeding, mast cells cause einflammatory
- clot with fibrin network, stratum basale cells migrate, phagocytic cells arrive
- mesh produced by fibroblasts, fibrin clot breaking
- epidermis complete, shallow depression fibroblast continues
intrinsic ageing affects
decreased cell activity and growth factors eg hormones
causes dermal thinning, wrinkles, white hair, high infection
extrinsic ageing affects
from sun, smoking etc
causes wrinkles, skin cancer
