anatomy 4

  1. Integumentary System
    Overall structure
    • pEpidermis (stratified squamous epith.)
    • pDermis (CT)
    • p(subcutaneous layer / hypodermis)
  2. Functions of integument
    • pProtection – physical, insulation
    • pPrevention of water loss
    • pTemperature regulation – capillaries, sweat glands
    • pMetabolic regulation – vitamin D, Ca++ homeostasis
    • pImmune defense
    • pSensory reception - touch, temp, pain, pressure, vibration
    • pExcretion - sweat
  3. Epidermis
    • pKeratinized stratified squamous epithelium (keratinocytes)
    • pStratum basale
    • nSingle layer of columnar to cuboidal cells attached to basement membrane
    • nAreolar CT deep to BM
    • nStratum basale cells undergo mitosis
    • pStratum spinosum
    • pStratum granulosum - keratinization
    • pStratum corneum – dead cells
  4. Stratum Basale
    • pOnly layer that is mitotically active
    • pSingle layer of cells directly adjacent to the dermis populated by three cell types:
    • 1.Keratinocytes – most abundant and produce a water-insoluble protein (keratin) that is strong and prevents the skin from dissolving in an aqueous environment
  5. 2.Melanocytes
    • Have long branching cytoplasmic processes that are distributed throughout this cell layer
    • Produce a black/brown/yellow-brown pigment that can absorb energy from the ultraviolet spectrum of light thus preventing damage to DNA of cells in this layer and possibly preventing a form of skin cancer
  6. Tactile cells
    – sensitive to touch
Card Set
anatomy 4
integumentary system