Functional histology of ectodermal structures Flashcards
What are the outer and inner layers of the skin?
Epidermis is the outer layer, dermis is the inner layer
What type of epithelium makes up the skin epidermis?
Stratified squamous keratinising epithelium
What are 2 benefits provided by epithelial strata in the epidermis?
Protection and waterproofing of skin
What is meant by keratinising epithelium?
The epithelium contains squamous cells called keratinocytes which produce keratin
How is the keratin layer organised in the epidermis?
Basket-weave pattern
How are individual keratinocytes in the epidermis attached to each other
Desmosomes
What is a desmosome?
Intercellular junction (resembles a ladder) that mediates cell-cell adhesion
When keratin overproduction occurs, how can this be identified by looking at the skin?
Thick layer of keratin causes scaly patch to form on skin
What is parakeratosis?
Incomplete maturation of keratinocytes, leading to abnormal retention of their nuclei
Why is keratin overproduced in the epidermis?
Increased rate of epidermal turnover causes parakeratosis
What substance provides strength to dermis?
Collagen
What substance allows dermis to stretch?
Elastin
What cell type can a schwann cell be classed as in terms of its structure?
Spindle cell
What wraps around the axon of a schwann cell to form the myelin sheath?
Cytoplasmic processes
What is the function of the myelin sheath of schwann cells?
Speeds up nerve conduction
