Skin layer overview Flashcards
What are the 3 layers of the skin?
epidermis, dermis, subcutis
What are the primary skin cells of the epidermis?
keratinocytes (primary), melanocytes, langerhans, Merkel cells
What is an important feature the epidermis lacks?
no blood vessels or nerve endings
What layer is primarily made of fibroblasts, collagen, and elastic cells?
dermis
If you were to bleed from a pencil stick, what layer are you in at minimum?
dermis
What layer of skin contains the fat?
subcutis
What is also found in the subcutis layer?
blood vessels and fibrous septae
What is the primary job of the epidermis?
primary barrier fxn, protection, and wound healing
What are the jobs of teh dermis and subcutis?
structural support, vascular support, innervation
How long does it take for a new epidermal layer to grow?
28+ days
What part of the epidermis do stem cells grow?
basal layer (shed from surface)
Describe the differentiation of the stem cells from the basal layer
cells terminally differentiate as they move upward
What is the order of the layers in the epidermis? (outside-in)
corneum, granulosum, spinosum, basale
What is important about hemidesmosomes?
basal cells adhere to the dermis (basement membrane zone) via hemidesmosomes
As the cells that are migrating from the basale layer to the spinous layer, what is important about their growth?
they stop dividing and start terminal differentiation
As the cells of the spinous layer develop, what improves the barrier function of the skin?
develops lipid from lamellar granules
Where are desmosomes located?
spinous layer of the skin
What is the function of the desmosomes?
spiny cells that adhere the KC to one another
The granular cell layer synthesizes what to be used in the outer cell layers?
profilaggrin
What type of granules are synthesized in the granular cell layer?
intracellular keratohyaline granules