Flashcards in The Structure and Function of the Skin Deck (122)
Where is the epidermis?
The outer layer
Describe the epidermis
Stratified cellular epithelium
Where is the dermis?
Beneath the epidermis
Describe the dermis
Where does the epidermis come from and how does it form?
Ectoderm cells form a single layer periderm. This gradually increases in layers of cells and the periderm cells cast off
How is the dermis formed?
From mesoderm below ectoderm
What are melanocytes
Pigment producing cells
Where do melanocytes migrate from
The neural crest
What 5 things does the skin consist of?
Give 4 examples of Appendages
What is the majority of the epidermis made up of and what does it contain?
keratinocytes. It contains structural keratins
What are the 4 types of epidermal cell layers
How is the regulation of epidermal turnover controlled
In what two scenarios is there a loss of control in the epidermal turnover
Histologically, what happens to the cells in psoriasis
Where do keratinocytes migrate from?
The basement membrane
How thick is the basal layer
One cell thick
What type of cell makes up the basal layer
What is the main feature of the basal layer
It is highly metabolically active
What are there lots of in the prickle cell layer
What connects to desmosomes
What is the granular layer made up of
2-3 layers of flatter cells
High lipid content
What is unusual about the cells in the granular layer
Cell nuclei are lost
What is the main function of the keratin layer
To provide a tight waterproof barrier to keep you from losing water
What common skin disease affects keratinocytes and what does it cause?
HPV - causes warts
Where are the mucosal membranes in the body
What are the 3 other types of epidermal cells
Melanocytes (basal & suprabasal)
Langerhans cells (suprabasal)
Merkel cells (basal)
At what stage do melanocytes migrate from the epidermis to the neural crest
In the first 3 months of foetal development
What are the organelles called that melanocytes contain