Integumentary system

  1. What is the epidermis made out of and where is it thickest?
    Stratified squamous keratinizing epithelial tissue and thickest on psalms and soles
  2. Define keratinizing?
    The protein keratin is produced and surface cells are dead
  3. What are squamous epithelial tissue?
    • Made of many layers of flat cells 
    • Mitosis takes place in the lower layers to replace the skin that has worn out at the top layer
  4. What happens in the stratum germinativum?
    • Lowest layer 
    • Mitosis takes place here, pushes older cells toward the skin surface
  5. What are Merkel cells?
    They are receptors for the sense of touch
  6. Why are the cells at the top dead?
    Because they have moved to far from the the capillaries and have no nutrients
  7. How is vitamin D produced?
    • It is produced by living keratocytes who produce  a cholesterol
    • that with exposure to UV light turns to vitamin D
  8. What do you call the outer most layer?
    Stratum corneum
  9. What makes the skin water proof?
    The presence of keratin as it prevents the entry of water
  10. What is a first degree burn?
    • A burn where only the superficial skin is burnt
    • Appears red due to vasodilation in the damaged area
  11. What is a second degree burn?
  12. What are Langerhans cells?
    They are dendritic cells
  13. Where are melanocytes found 
    in the lower epidermis?
  14. What is the function of melanocytes?
    Produce a protein, pigment called melanin on exposure to UV light
  15. The function of dendritic cells?
    They are antigen-presenting cells, they present it to the surface of t-cells

    • Phagocytize foreign material
    • and stimulate an immune
    • response by lymphocytes
  16. What is the dermis made up of?
    An irregular type of connective tissue

    Strength and elasticity are characteristics
  17. What do the call the junction between the dermis and epidermis?
    • the papillary layer
    •  Capillaries are abundant here to nourish not only the

    dermis but also the stratum germinativum.
  18. Name all the layers of the integumentary system
    Stratum corneum, lucidum, granulosum, spinosum, basale
  19. What is the appearance and function of the stratum spinosum
    Appears to be covered in thorn like spikes, providing the skin with strength and flexibility
  20. What is the appearance and function of the stratum granulosum?
    • Site of keratin formation
    • has keratinocytes
    • keratohyalin gives it it's granular appearance
  21. Where is the stratum lucidium found?
    • In the soles, palms and fingertips.
    • Made up of dead keratinocytes
  22. What provides water repellent action?
    the Lamellar granules, they are continuously shed and replaced
  23. What do langehanns cells do?
    • Regulate immune reactions in the skin
    • Ingest antigens and present them to the cells of the immune system
  24. What is the dermis tissue composed of?
    Connective tissue, blood vessels, nerves, glands and hair follicles
  25. What are the cells in the epidermis?
    • Keratinocytes
    • Merkel cells
    • Langerhans cells
    • Melanocytes
  26. What do the elastic fibres in the dermis help with?
    strength and elasticity
  27. What is the subcutaneous tissue made up of?
    an insulating layer of fat and blood vessels
  28. What is the function of the subcutaneous tissue?
    Maintain body temperature and offers protection to all the organs
  29. What are the sweat glands used for?
  30. What is the function of hair?
    Protection, thermoregulation and sensing light touch
  31. What is hair composed of?
    elongated  dead keratinized cells that are bound by extracellular proteins
  32. Where is hair not found?
    Found everywhere on human body except palms, soles, lips, nipples, parts of external genitalia, and distal segments of fingers and toes
  33. What is the hair shaft?
    the superficial portion that extends out the skin
  34. What is the hair root?
    the portion that penetrates the dermis
Card Set
Integumentary system