VIII - Skin Flashcards
Outermost layer of integument, stratified squamous epithelial layer of ectodermal origin, devoid of blood vessels and consists of 4-5 layers
epidermis
Connective tissue layer of mesodermal origin below the epidermis and its basement membrane
dermis
Dermis: loose, comparatively cell-rich connective tissue, fills the hollows at the deep surface (dermal papillae) of the epidermis, capillaries are frequent, collagen fibers are finer
papillary layer
Dermis: appears denser and contains fewer cells, thick collagen fibers that aggregate into bundles
reticular layer
Layer of loose vascular connective tissue infiltrated by adipocytes
hypodermis
Skin: production of keratin protein, squamous epithelial cells
keratinocyte
Skin: important in formation of endogenous sunscreen, sound in basal layer and in hair follicles
melanocyte
Skin: epidermal dendritic cells, antigen presenting cells
Langerhan cells
Skin: serve as mechanoreceptors or a neuroendocrine function
Merkel cells
Disorder in which melanocytes are destroyed, autoimmune
Vitiligo
Disorder in which melanocytes are unable to synthesize melanin either due to abscence of tyrosinase activity or inability to take up tyrosine
Albinism
Skin Layers from most superficial
corneum, lucidum, granulosum, spinosum, basale
Skin Layers: superficial stratum layer consisting of 20-30 layers of dead, flat, anucleated and cornified/keratinized cells filled with keratin filaments (horny cells) embedded in a densematrix of proteins
Stratum Corneum
Skin Layers: spaces between cells are filled with lipids making a continuous membrane, protects against friction and water loss
Stratum Corneum
Skin Layers: 2-3 layers of transitional cells of flat eosinophilic anucleated cells, only found in regions of thick stratum corneum of palms and soles
Stratum Lucidum
Skin Layers: polygonal cells filled with basophilic keratohyaline granules, only 1 layer is seen in thin skin, multiple in thick skin
Stratum Granulosum
Part of stratum granulosum that produces a lipid-rich impermeable layer around cells
lamellar granules
Skin Layers: multilaminar layer of cuboidal-like cells that are bound together by numerous desmosomal junctions
Stratum Spinosum
Antigen presenting cells in stratum spinosum, contains Birbeck granules
Langerhan cells
Single layer of cuboidal to low columnar cells in contact with basement membrane, attached to the basal lamina via hemidesmosomes, mitotically active
Stratum Basale (Germinatum)
Cells in the stratum basale with intense mitotic activity
melanocytes, Merkel cells
Sensory Recetor Capsule: Merkel cells
unencapsulated
Sensory Recetor Capsule: free nerve endings
unencapsulated
Sensory Recetor Capsule: root hair plexuses
unencapsulated
Sensory Recetor Capsule: Meissner corpuscles
encapsulated
Sensory Recetor Capsule: lamellated (Pacinian) corpuscles
encapsulated
Sensory Recetor Capsule: Krause end bulbs
encapsulated
Sensory Recetor Capsule: Ruffini corpuscles
encapsulated
Simple branched acinar holocrine grands, found in the dermis except in the palms and soles, lubricate hair and cornified layers of the skin to minimize dessication
sebaceous glands
Sebaceous Glands: hairy areas
pilosebaceous unit
Sebaceous Glands: glabrous skin
sweat pores
Sudoriferous Glands
Sweat Glands
Sweat Glands: coiled tubular glands, in most areas of the skin, opens in skin surface, clear, odorless (H2O, NaCl), active throughout life, body temperature regulation (cholinergic), emotional sweating (adrenergic)
eccrine, merocrine
Sweat Glands: coiled tubular glands, axillary, areolar, anal, hair follicles, viscous, odorous, active at puberty, pheromones (adrenergic)
apocrine
When apocrine sweat or sebaceous glands are occluded and infected
Hidradenitis Suppurativa
Abnormal aggregation of cells that may be seen in squamous cell CA
keratin pearls
