Chapter 1- Epidermis Flashcards
Name the four distinct cell types within the epidermis
- Keratinocytes 2. Melanocytes 3. Langerhans cells 4. Merkel cells
Keratinocytes compose what percentage of epidermal cells?
85%
Melanocytes compose what percentage of epidermal cells?
5%
Langerhans cells compose what percentage of epidermal cells?
3 to 8%
Merkel cells compose what percentage of epithelial cells?
2%
The epidermis is divided into 5 layers. Name them from inner to outer
- basal layer (Stratum basale) 2. spinous layer (stratum spinosum) 3. granular layer (stratum granulosum) 4. clear layer (stratum lucidum) 5. horny layer (stratum corneum)
The epidermis of cats and dogs in haired skin is how many nucleated cell layers (not counting the horny layer)?
2 to 3
The haired epidermis of cats and dogs is how thick? (range)
0.1 to 0.5 mm
Where is the thickest epidermis found and how thick does it measure there?
footpads and nasal planum- 1.5 mm
The footpad epidermis is smooth in dogs or cats? Papillated and irregular in dogs or cats?
Cats- smooth; Dogs- papillated and irregular
Projections of the epidermis into the underlying dermis are called____ ______.
rete ridges
What are rete ridges?
projections of the epidermis into the underlying dermis
Where are rete ridges NOT found?
they are NOT found in the normal hair bearing skin of cats and dogs
Where are rete ridges found?
foot pad, nasal planum epidermis, scrotum
Name the cell types that compose the stratum basale
single row of columnar to cuboidal cells
Where do the columnar and cuboidal cells of the stratum basale rest upon? (what structure)
basement membrane
Basement membrane separates what two layers?
dermis from the epidermis
The columnar and cuboidal cells of the stratum basale are mostly what distinct cell type?
keratinocytes