skin Flashcards
largest organ in the body
skin
thickest skin
soles of the feet
thinnest skin
upper and lower eyelids
dark pigment that protects the epidermis from ultraviolet radiation
melanin
sweat is produced by?
eccrine glands
serves as personal identification; patterns assumed by ridges and intervening sulci
dermatoglyphics
brownish black pigment
eumelanin
similar pigment found in red hair
pheomelanin
where is melanin synthesized?
tyrosine and cystine in the melanosomes
congenital melanin disorder caused by defect in tyrosine
albinism
skin pigmentation in affected patches due to decreased activity of melanocyte
vitiligo
mediates and contacts allergic response in the skin and delayed hypersensitivity reaction
dendritic cells
where are dendritic cells derived from?
bone marrow and blood borne cells
responsible for sensory mechanoreceptor
merkel cells
where are merkel cells derived?
neural crest cells
most superficial layer of the epidermis
stratum corneum
process of continuously shedding cells
desquamation
only seen in thick skin; consists of thin translucent layer of extremely flattened eosinophilic cells
stratum lucidum
3-5 layers of flattened polygonal cells undergoing terminal differentiation
stratum granulosum
composed of stratum basale and stratum spinosum
malphigian layer
deepest layer of epidermis; site of active mitosis and contains melanocytes
stratum basale
tonic receptors for sustained light touch and for sensing an object’s texture
merkel cells
responds to high and low temperatures, pain, and itching
free nerve endings
web of sensory fibers surrounding the bases of hair follicles in the reticular dermis
root hair plexus
initiate impulse when light-touch or low frequency stimuli against skin
meissner corpuscle
found in penis and clitoris
krause end bulbs
stimulated by stretch or twisting the skin
ruffini corpuscles
second most common tumor arising on sun exposed skin
squamous cell carcinoma
most common invasive cancer in human
basal cell carcinoma
