Integument Flashcards
What is the difference between thick and thin skin? (4)
Thick skin is glaborous (thicker epidermis), thinner dermis, hairless and no apocrine sweat galnds.
Thin skin has thin epidermis, thicker dermis, has sebaceous glands, apocrine sweat glands and hair structures.
What are the 5 layers of epidermis? (5)
- Stratum Cornium (Horn Cell layer)
- Stratum Lucidum (only in thick skin)
- Stratum Granulosum (Granular layer)
- Stratum Spinosum (prickle cell layer)
- Stratum Basale (Basal cell layer)
What are the type of cells found in the epidermis? (4)
- Keratinocytes
- Melanocytes
- Langerhans Cells (for immune function)
- Merkel Cells (for Sensory Function)
What immunohistochemistry is used to highlight Keratinocytes?
p40, p63, CK5/6, CK14
Where do melanocytes originate?
Where is Melanin found and how does it migrate? (4)
They originate from neural crest (this is formed from ectoderm during embryology).
They are found around basement membrane.
The melanin is produced in melanosome. The melanin is then delivered to 36 keratinocytes via dendrites.
Where do Langerhan cells originate from?
What type of cells are they and what do they do? (3)
Originate from Bone marrow.
They are dendritic cell (antigen presenting). They serve as immune sentinels in skin microbe.
Where do Merkel cells originate?
What type of cells are they and what do they do? (3)
Originate from neural crest.
They are associated with sensory nerve endings.
They mediate light touch.
What structures make up a pilosebaceous unit? (3)
Hair, sebaceous glands, and smooth muscle.
Associated Apocrine sweat gland.
(eccrine in hairless thick skin).
How does a BCC occur? (3)
It is a tumour of hair follicle origin.
It is related to UV light exposure. It is locally destructive but unlikely to metastasize.
How is temperature regulated in skin? (2)
Vasodilation: increases blood flow, leading to loss of heat.
Evaporation of sweat.
