Skin Structure and Function Flashcards
(18 cards)
what is the top layer of skin called and what is it made of?
epidermis and stratified squamous epithelium
what is the epithelium mostly composed of? and where do these cells originate from?
keratinocytes which originate from a proliferating basal layer
what is the fate of keratinocytes
they differentiate and migrate out to the surface to be shed as dead, flattened squames
what is synthesised in the granular layer and secreted to form a watertight intercellular layer
lipids
purpose of filaggrin
acts as a natural moisturising factor keeping the skin hydrated and pliable
pigment producing cells from neural crest
melanocytes
formed from mesoderm below ectoderm
dermis
epidermis germ cell origin
ectoderm
what layers of the skin are present at 4 weeks
periderm
basal layer
dermis (corium)
what layers of the skin are present at 16 weeks
keratin layer granular layer prickle cell layer basal layer dermis
what else is present in the skin at 26 weeks
hair follicle
arector pill muscle
sebaceous gland
melanocyte
what are Blaschko’s lines?
developmental growth pattern of skin - not following vessels, nerves of lymphatics
name 4 cells found in the epidermis
keratinocytes, melanocytes, langerhans cells, merkel cells
how many layers are in the epidermis
4
what do langerhans cells do
tissue-resident macrophages that form a network of cells across the epidermis of the skin, but which have the ability to migrate from the epidermis to draining lymph nodes (LN). Their location at the skin barrier suggests a key role as immune sentinels
what do merkel cells do
slowly adapting mechanoreceptors that mediate the senses of touch and hair movement
keratinocytes are involved in…
skin repair
how many days for keratinocytes from migrate from basement membrane to top?
28 days
