Exam 1 Flashcards
what is the largest organ in the body
skin
what are the three layers of the skin
epidermis
dermis
panniculus
what are the functions of the skin
protective barrier
regulates temp and blood pressure
produces vit D
sensory organ
stores nutrients
absorptive surface
innate and adaptive immunity
what kind of epithelium is the epidermis
stratified squamous with keratinocytes
how long for renewal in the haired skin
one month
what are the layers of Strat squam
stratum corneum
stratum lucidum (in non haired)
stratum granulosum
stratum spinosum
stratum basale
what is in the stratum spinosum
desmosomes
what cells are in the epidermis
melanocytes
langerhans cells
merkel cells
what are the melanocytes
in the basal layer and then lower s. spinosum
melanin
what are the langerhans cells
bone marrow-derived cells of monocyte-macrophage lineage
antigen presenting cells
merkel cells
neuroendocrine cells in the basal layer
regions of the body with high tactile sensitivity (digits and lips)
likely related to paracrine or autocrine control of keratinocytes or hair follicles
what is the difference between haired and non haired dermal epidermal junction
in non hair there are papillae that confers resistance to shearing
in haired skin, the junction is smooth
basement membrane zone layers
basal cells
basement membrane
dermis
where are the the hemidesmosomes
basal cells
what type of collagen is in the lamina densa
collagen type IV
what are adnexal structures
hair follicles
sebaceous glands
apocrine glands
what are the functions of the panniculus
adipose tissue
flexibility
insulation
shock absorption in footpads
hair cycle
anagen: growing stage
catagen: transitional phase
telogen: resting stage
exogen: old hair shedding
what kind of hair follicles do cattle and horses have
evenly distributed simple follicles
what kind of hair follicles do pigs have
simple follicles in clusters
what kind of hair follicles do dogs, cats, and goats have
compound follicles composed of primary follicles and smaller secondary follicles
what kind of hair follicles do sheep have
simple follicles in hair areas and compound in wool areas
what are sinus hairs
tactile hairs
simple follicles with blood-filled sinus between the inner and outer layers of the dermal shealth
what glands are open into the hair follicles
sebaceous glands