A&P 201 unit 2 skin

  1. what is the integumentary consist of?
    • skin
    • hair
    • nails
    • glands
  2. where are glands found?
    found in the dermis of the skin which is composed of connective tissue
  3. the skin is composed of what 2 layers?
    • dermis
    • epidermis
  4. what are the appendages of the skin?
    • glands
    • arrector pili muscles
    • and hairs
  5. what are the skins nervous structures?
    • Meissner's corpuscles
    • pacinian corpuscles
    • and free nerve endings
  6. what is the epidermis composed of?
    kerartinazed stratified squamous epithelium
  7. where are keratinocytes found?
    they produce a fibrous protein called?
    • 1. found in the deepest layers of the epidermis
    • 2. keratin
  8. where are melanocytes found?
    what do they produce?
    • 1. found in the stratum basale (basal layer) of the epidermis
    • 2. produce melanin,a dark skin pigment, it helps protect skin cells from cancerous uv rays
  9. where are Merkel cells found?
    what do they come into contact with?
    what are they invovled in?
    • found in the stratum basale
    • come in contact with sensory neurons
    • involved in touch sensation
  10. what are the langerhan's cells?
    where do they migrate to?
    • they are macrophage like cells that provide a immune response against foreign cells that invade the body surface
    • they migrate from the red bone marrow to the stratum spinosum
  11. what is the stratum corneum?
    • outter most layer of the epidermis
    • composed of a tightly packed layer of dead cells heavily kertanized
    • layer is very thick in thick skin(palms,or soles of feet)
  12. what is the stratum lucidum?
    • layer of epidermis appears somwhat clear
    • most cells are dead
    • its greatly reduced in thin skin
    • easily seen in thick skin
  13. what is the stratum granulosum?
    • layer of epidermis
    • appears granular
    • composed of living cells
  14. what is the stratum spinosum?
    • layer of epidermis
    • composed of spiny shaped cells
    • contains Langerhans's cells
    • composed of living cells
  15. w
  16. what is the stratum basale?
    • innermost layer of the epidermis
    • a single cell thick
    • the most active cell division occurs here
    • contains melanocytes and Merkel cells
    • composed of living cells
  17. how does the epidermis grow?
    from the bottom up (like all epithelial tissue)
  18. the growth of the epidermis?
    • mitosis occurs in the stratum basale
    • living cells pushed towards the surface
    • living cells kertanized flatten and die as they get closer to the surface
    • dead cells are sloughed off at the surface
  19. what is the dermis composed of?
    dense irregular connective tissue richly supplied with blood vessels and nerves
  20. what does the papillary layer contain?
    • layer of the dermis
    • contains the dermal papillae
  21. what is the dermal papillae?
    • helps hold the epidermis to the dermis
    • increases surface area for exchange of nutrients with the epidermis
    • contributes to fingerprints
  22. what is the reticular layer?
    • 80% of the thickness of the dermis
    • found below the papillary layer
    • contains most of the structure of the dermis
  23. nervous structures of the dermis;
    Messner's corpuscles?
    Pacinian corpuscles?sensory nerve/free nerve endings?
    • 1. found in the dermal papillae involved in light touch sensation
    • 2. deep in the dermis sensative to deep pressure
    • 3. involved in the sensation of the warmth, coolness, pain, tickling and itching
  24. what is the hypodermis?
    what are its functions?
    • "below the skin" also called the superfical fascia
    • 1. site for storage of fat
    • 2. helps to loosely anchor the skin to mostly muscles
    • 3. helps to insulate the body to prevent heat loss
  25. what three pigments contribute to skin color?
    • melanin
    • carotene
    • hemoglobin
  26. overview of glnad types?
    they are all eithelial in orgin but are found in the underlying connective tissue
  27. overview of exoccrine glands?
    • have a duct
    • make an external secretion
    • examples are oil and sweat glands of the skin
  28. overview of endocrine gland?
    • do not have a duct
    • make an internal secretion
    • secrete hormones into the blood to be carries elsewhere in the body
    • collectively form the endocrine system
  29. where are sweat glands located (sudoriferous glands)?
    distrubuted over almost the entire body surface
  30. overview of eccrine sweat glands?
    • most numerous type of sweat gland
    • produce true sweat in response to:
    • elevated temp. nervousness spicy foods,
    • composed of simple cubodial epithelium
  31. properties of the apocrine gland?
    • found in the axillary anal and genital areas
    • produce a milky or yellowish colored sweat
  32. what do ceruminous glands produce?
    • found in the ears
    • produce ear wax
  33. propeties of sebaceous glands?
    • found in all skin except palms and soles of feet.
    • produce an oily substance called seabumwhich collects dirt softens and lubricates hair keeps epidermis from crcking kills bacteria and slows water loss
  34. what is hair composed of?
    what are the functions?
    • dead kertanized epithelial cells
    • sense things that lightly touch the head
    • protects the head from direct sunlightin the summer and heatloss in the cold
    • eyelashes shield the eyes
    • nse hairs filter particles from incoming hair
  35. shaft vs root?
    • shaft is the part coming out of the skins surface
    • the root is below
  36. hair follicle vs the hair?
    hair is enclosed in a hair follicle
  37. cross section:
    hair follicle?
    • central core of hair
    • surrounds the medulla of the hair
    • outtermost layer of the hair
    • surrounds the hair
  38. longitudinal section:
    hair matrix?
    hair papilla?
    hair follicle?
    hair bulb?
    • region of high cell divison growing region of hair
    • produce pigment of hair
    • stimulates hair growth and supplies nutrients to growing hair
    • surrounds hair
    • expanded end of the hair follicle
  39. what is teh arrector pili muscle?
    • attaches to the hair follicle
    • contraction of muscle in response to cold or fear causes the hair to stand erect (goose bumps)
    • useful in animals to provide warmth and look dangerous to ememies
  40. what are the nails composed of?
    • like the hair is composed of dead keratinized epithelial cells
    • and hard keratin
  41. free edge?
    the most distal part of the nail
  42. hyponychium?
    the area below the free edge of the nail
  43. nail body?
    the visable attached part
  44. nail root?
    the proximal part (embedd in the skin)
  45. eponychium?
    the cuticle
  46. nail matrix?
    • the actively growing part of thr nail
    • also where the highest mitosis occurs
  47. lunula?
    the white cresent area
  48. functions of the integumentary system?
    • cushions and insulates deeper organs
    • protects body from bumps scrapes and cuts
    • protects body from chemicals and changes in temp.
    • retards water loss
    • acts as a mini excretory system
    • screens out uv rays from the sun
    • contains sensory receptors associated with nerve endings
    • makes vitamin D in the presence of sunlight
  49. temp. regulation:
    when bloodvessels in the skin dialate?
    when blood vessels constrict?
    • blood is shunted to the bodies surface in order to cool the body
    • blood is shunted away from the skin therefore maintaining a warmer temp.
  50. how is the body cooled?
    by sweating also called evaporative cooling
  51. where are stencells found?
    in both epithelial and connective tissue of the skin
  52. 4 stages of skin regeneration after energy?
    • bleeding occurs at the injury site there is an inflammatory response
    • blood clot formedand scab produce macrophages remove debri in the scab fibroblasts invade deeper areas of the injury
    • the injury is surrounded by epithelial cells by a week, phagocytes disenagrate the scab
    • scab is shed epidermis is complete, fibroblasts continue to create scar tissue
  53. blister?
    caused byshort term but acute trauma resukts in the seperation of teh epidermal and dermal layers by a fluid filled pocket
  54. what causes freckles and moles?
    local accumulations of melanin
  55. what causes a tan?
    melancytes increase their activity when the skin is exposed to sunlight.
  56. what causes bruises?
    reveals where blood escaped from the circulation and clotted beneath the skin
  57. skin cancer?
    a malignent tumor of the skin caused by over exposure to uv rays
  58. what is a basal cell carcinoma, where does it occur?
    • most common skin cancer
    • grows very slow
    • seldom metastasizes
    • occurs in the stratum basale
  59. squamous cell carcinoma?
    • arises in the stratum spinosum
    • if caught early and removed the overall cure rate is 99%
  60. malignent melanoma?
    • the most dangerous type of skin cancer
    • a cancer of melanocytes often arises from existing moles
    • can metastasize very quickly
    • early detection is vital
  61. ABCDE rule of moles/
    • assymetry:the 2 sides do not match
    • border: the borders have indentations
    • color: contains several colors (blk. brown tan blue red.
    • diameter: larger than 6mm in diameter the size of a pencil eraser
    • elevation: elevated above the skin surface
  62. wart?
    a benign tumor of the skin
  63. what is a tumor?
    an uncontrolled rapid growth of cells
  64. first degree burn ?
    • only the epidermis is damaged
    • symptoms are redness swelling pain
    • example sunburn
  65. second degree burn?
    • injury to the epidermis and upper dermis
    • symptoms like 1st degree but aslo blisters
  66. third degree burn?
    • most serious type
    • consumes the entire thickness of the skin
    • a skin graft is usually needed
  67. tattoo?
    • temp. tattoo's only color the epidermis
    • perm. tattoo color the dermis. the dermis doesnt slough off so it makes it permanent
  68. what causes acne?
    caused by blocked sebaceous glands that have been infected by bacteria
  69. effects of aging on the integ. system:
    • epidermis thins making injury happen more
    • melanocytes producton declines leaving eldery pale
    • sebaceous gland activity declines leaving skin dry and flaky
    • sweat glands less active leaving the elderly prone to overheating
    • hair follicels decline causing gray dry hair
    • dermis becomes thin less collegan leads to wrinkles
    • low blood supply takes longer to repair
Card Set
A&P 201 unit 2 skin
A&P 201 unit 2 skin