Skin Flashcards
Functions of skin
- protection from external damage
- metabolic
- thermoregulation
- sensation
- barrier
How is skin used in metabolism
Synthesises vitamin D3
What are the 3 layers of the skin
Epidermis
Dermis
-HYpodermis
What does the epidermis contain
Stratified squamous epithelium (keratinocytes)
What does the dermis contain
Dense irregular connective tissue
Fibroblasts, collagen 1, elastin, blood, nerves and receptors
What is the dermis divided into
Papillary and reticular dermis
What does the hypodermis contain
Adipose tissue and main blood supply
Layers of epidermis going from bottom to top
Keratinocyte layers:
Stratum basale Stratum spinosum Stratum granulosum Stratum incidum Stratum corneum
What are the barriers found in skin
Tight junctions
Demsosomes and hemidesmosomes
Keratin
PHospholipid
What concerns can occur in skin
- Basal cell carcinomas
- Squamous cell carcinoma
Who can skin carcinomas affect
People of all skin colours
What are melanocytes
Pigment synthesizing cells which decide skin and hair colur
What do melanosomes in cytoplasm do
They contain melanin and are passed to keratinocytesand scatter UV light
What are langerhans cells
Dendritic antigen presenting cells
Where are langerhans found
Spinal chord
What do langerhans cells do
Migrate to lymph nodes and communicate with immune system
What is the function of Merkel cells
Neuroendocrine function
Where are Merkel cells found
IN stratum basale in areas of ‘touch’
What causes lentigo maligna
Increased number of melanocytes
What causes albinism
Missing enzyme tyrosinase used to make melanin
How to tell if a mole is cancerous
- Irregular border
- Range of colours
- Diameter
How do junctions help skin stay on
Hemidesmosomes (adhere dermis to epidermis)
How does interdigidation help skin stay on
Interdigitation between epidermis and dermis increases surface area
How does the basement membrane help skin stay on
Sits between epidermis and dermis
