SKIN ANATOMY I Flashcards
1/ Describe layers of the skin 2/ Describe functions of the skin 3/ Understand basic classification of burns and potential complications
what are the 7 keywords for function of skin?
Protect - Excrete - Maintain - Produce - Synthesize - Storage - Detect
what skin protects against?
protect underlying tissue and organs against impact, abrasion, fluid loss and chemical attack
excretion of skin?
salt, water, organic waste by integumentary glands
what does skin produce?
melanin and keratin
melanin vs keratin?
melanin: protect from ultraviolet radiation
keratin: protect from abrasion and water repellent
what is the purpose of vitamin D3 synthesis of skin?
vitamin D3 = steroid that is subsequently converted to calcitriol = a hormone important to normal calcium metabolism
where is lipids being store?
- adipocytes in dermis
- adipose tissue in subcutaneous layer
what does skin detect?
touch, pressure, pain, temperature stimuli –> relay the information to the nervous system
what does it mean to say skin is a composite organ?
it is made up of all 4 tissue types
3 layers of skin from superficial to deep
epidermis - dermis - hypodermis
what are the 2 layers that made up the cutaneous ?
epidermis and dermis
what is subcutaneous also referred to?
hypodermis (adipose tissue)
the 3 main characteristics of the epidermis?
- stratified barrier
- mostly keratinocytes
- avascular
the 2 main characteristics of the dermis?
- protein fibres –> strength
- vascular
types of epithelia
- simple: squamous - cuboidal - columnar
- stratified: squamous - cuboidal - columnar
simple vs stratified
simple = single layer cell
stratified = stacked
what kind of epithelia is epidermis?
stratified squamous
4 main layers of epidermis (+ 1 extra) from superficial to deep
- stratum corneum
(- stratum lucidum) - stratum granulosum
- stratum spinosum
- stratum basale
what is the difference between thin and thick skin?
- 1 extra epidermal layer, thin skin doesn’t have stratum lucidum
- no hair at thick skin
examples where can find thick skin
palms of hands, soles of feet
characteristic of stratum corneum
- dead, dried-out hard cells
- no nuclei
characteristic of stratum granulosum
- contains granules that promotes dehydration of the cell and crosslinking of keratin fibre
- waxy material secreted into the intercellular spaces
characteristic of stratum spinosum
- desmosomes link cells together
- cells increasingly flattened as they move upward
characteristic of stratum basale
- columnar regenerative cells
- basal cell divides –> daughter cell migrates up to replenish the layer above
what part of epidermis promotes dehydration of cell and crosslinking of keratin fibre
the granules in stratum granulosum
what anchor neighboring
cells in epidermis
desmosomes (at stratum spinosum)
what anchor epidermis to dermis
hemidesmosomes (stratum basale to dermis)
what is the type of junction that connects epidermis to dermis
tight junction
what layers contain stem cells
stratum basale of the epidermis
what do the stem cells in the epidermis produce?
keratinocytes
what are the 2 layers of dermis from upper to deeper?
- papillary layer
- reticular layer
dermis main characteristics?
- below epidermis, anchor via hemidesmosomes
- not shed
what is the papillary layer mean?
highly vascularised tissues for nourishment
what consisted in both layers of the dermis?
blood vessels. lymphatics, sensory nerve fibres and accessory structures
what reticular layer mean?
- mesh-like structure
- collagen and elastin fibre for strength
what layer in dermis is mesh-like of collagen and elastin
reticular - support strength
name of the 2 plexuses of the dermis?
cutaneous and subpapillary
what presents at junction of dermis/hypodermis?
cutaneous plexus - network of blood vessels
what is the funtion of cutaneous plexus?
supplies the hypodermis, deeper dermis, including the capillaries for hair follicles and sweat glands
what branches from cutaneous plexus?
subpapillary plexus
characteristic of subpapillary plexus?
lies deep to the papillary layer of dermis
what does subpapillary plexus do?
network of blood vessels providing O2 and nutrients to upper dermis and epidermis
what layer is not considered part of skin?
hypodermis - referred as ‘subcutaneous’ layer
what dominates the hypodermis
adipocytes that produce subcutaneous fat
what is the purpose of subcutaneous fat?
- stores energy
- provides insulation
which layer is a common site of injection?
hypodermis - using hypodermic needles
what layer does first-degree burn?
superficial - outer layer of epidermis
red/pink, dry, painful and no blisters are signs of which type of burn?
first-degree
skin remains a water and bacterial layer if which burn-degree happened?
first
takes how long for first degree burn to heal?
3-10 days
which layer is being affected in second degree burn?
epidermis + varying amount of dermis
signs of second degree burn are?
painful, moist, red and blistered
how long it takes to heal second degree burn?
1-2 weeks with good dressings
what are the further symptoms if you get deep second degree burn?
may include whiteish waxy looking areas
hair follicles and sweat glands may remain intact
may have some loss of sensation and scarring
which burn degree has a full thickness burns? what does that mean?
third-degree burn
subcutaneous tissue (may inivolve muscle and bone) burn
varied colour from waxy white through to deep red and black is sign of which burn degree?
third-degree
what happens to skin with third-degree burn?
hard, dry, leathery
why can’t we feel pain in third-degree burn areas?
sensory nerve endings are destroyed
third degree burn complications?
may required skin grafting
weeks to regenerate and scarring
