Flashcards in Skin Deck (28):
hairy skin is missing what layer?
the cells of the stratum basale are linked to the basal lamina via _________
what is the thickest epithelial layer?
what are tonofibrils?
give mechanical strength to epithelium located in the stratum spinosum
what are lamellar granules?
membrane bound tubes that undergo exocytosis producing lipid rich barrier around cells to protect against water loss
what layer of epidermis do organelles disappear?
what are melanocytes formed from?
what occurs in the stratum corneum?
aggregated keratin filaments are cross linked forming squames and serving as a scaffold for lipids and proteins that for a barrier.
brown or black pigmentation
pink or red pigmentation
where are melanocytes located?
on the basal lamina of the stratum basale - not in the dermis!
depigmentation caused by loss / increased activity of melanocytes
how do moles form? proper name?
melanocytes divide normally for form theses - metaplasia
-benign menanocyte nevi
where are merkel cells located?
where are langerhans cells located?
what type of collagen is found in the papillary dermis?
type 3 collagen
-lots of cells and elastic fibers
what type of collagen is found in the reticular dermis?
type 1 collagen
-thick elastic fiber and few cells
what provides tactile sense in the dermal papillae?
what provides a sense of vibration and pressure in the hyprodermis?
how does aging affect the skin?
-increased cross linking of collagen
-loss of elastic fibers
-dermis and epidermis are more loosely bound
-keratinocyte turnover decreases
what three things are located in the hypodermis?
blood vessels, adipose tissue, pacinian corpuscles
where do eccrine gland open to?
how do both eccrine and apocrine sweat glands release their contents?
via merocrine glands = exocytosis
where are apocrine glands located?
auxilla, areolar region, anal regions
what is the difference in the lumens of eccrine vs apocrine glands?
eccrine glands - reabsorb salts and occluded
apocrine glands- big open lumen
how do sebaceous glands release their contents?
halocrine secretion - cell dies and it ruptures
type of collagen found in the papillary dermis vs. the reticular dermis?
papillary dermis- type 3 collagen
reticular dermis - type 1 collagen