Endo Week 1 Flashcards
How does the skin aid in photoprotection?
Urocanic acid and melanin absorb UVa and UVb
Describe vitamin D production in the skin?
Previtamin D3 is formed, which is isomerized to vitamin D3
What are the layers of the epidermis?
S. corneum, S. lucidum, S granulosum, s. spinosum, s. basale, dermis
What are epitrichial sweat glands
associated with a hair follicle
What are keratinocytes>
Produce extracellular lipids
What is a hemidesmosome
Anchors the epidermis to the dermis, link between keratin intermediate filamens and interstitial collagen of dermis
Which layers are absent in haired skin
Stratum lucidum and sometimes stratum granulosum
What is an epidermal melanin unit?
Melanocytes immersed in epidermis with close contact to defined number of keratinocytes
Which species has higher density of hair follicles- sheep or cat?
Cat
What is the difference between primary and secondary hair follicles?
Primary have the bulb deep in ther dermis and associated sebaceous, sweat gland and arrectoy pili musclces.
Secondary are smaller, not as deep and may have sebaceous glands but not the others
What is anagen phase?
The growth phase where new hair is produced under previous hair i deep dermis
What type of hair growth do dogs and cats undergo?
Telogenic growth
What is wave shedding?
Shedding and regrowth at specific areas of the body with gradual spread of new growth
Where do you find vibrissae hairs?
Nose, above eyes, lips
What hormones stimulate hair growth?
Melatonin, thyroid and growth hormone
