Integumentary System.txt

  1. Name and briefly describe the main components of skin.
    • Epidermis:
    • Keratinized, stratified squamous epithelium
    • Avascular
    • Dermis:
    • Dense, irregular connective tissue(some loose, areolar connective tissue)
    • Vascular, supplies O2 and nutrients to epidermis above
    • Hypodermis (superficialfascia):
    • Subcutaneous tissue(just deep to dermis)
    • Technically not part of skin
    • loose areolar connective tissue
    • fuel storage, insulation, protection, anchors skin underlying muscle
  2. What is the “hypodermis”?  Describe its structure and function.  Is it part of the skin?
    • Subcutaneous tissue(just deep to dermis)
    • loose areolar connective tissue
    • Technically not part of skin
    • fuel storage, insulation, protection, anchors skin underlying muscle
  3. Describe in detail the structure of the epidermis, include the layers and the functions of the main cell types found in this tissue.
    • Stratum corneum 
    • Most superficial layer; 20-30 layers of dead cells,essentially falt membranous sacs filled with keratin.
    • Stratum granulosum
    • Typically five laters of flattened cells, organelles deteriorating; cytoplasm full of lamellar granules (release lipids) and keratohyaline granules.
    • Stratum spinosum
    • Several layer of keratinocytes unified by desmosomes. Cells contain thick bundles of intermediate filaments made of pre-keratin.
    • Stratum basale
    • Deepest epidermal layer;one row of actively mitotic stem cells;some newly formed cells become part of the more superficial layers. See occasional melanocytes and dendritic cells.
  4. Describe in detail the structure of the dermis.
    • Papillary layer-thin, superficial
    • loose,areolar connective tissue
    • dermal papillae contain touch receptors"Meissner's corpuscles"
    • Reticular layer-(thick, deep)
    • Dense, irregular connective tissue
    • Collagen and elastic fibers (give skin strength, stretch-recoil ability)
  5. What are fingerprints?
    • Epidermal ridges
    • Collagen fiber running in different directions
  6. What determines skin color?
    • Three pigments contribute to skin color:
    • Melanin
    • Carotene
    • Hemoglobin
  7. Briefly describe the skin disorders psoriasis, albinism, and vitiligo
    • Albinism:Inherited inability to produce melainin
    • Vitiligo-Disease that causes loss of melanocytes from skin
    • Psoriasis: keratinocytes in ithe stratum basale of the pidermis divide more rapidly,shed prematurely and produce abnormal keratin
  8. Name and describe the 3 cell layers of hair.  What layer do hair conditioners work on?
    • Medulla: is central core
    • Cortex: surrounds medulla
    • Cuticle: is outermost layer

    Hair conditioners work on cuticle because it the outermost layer.
  9. Name the muscle in charge of producing "goosebumps" in reaction to cold or fear.
    Arretor pilli: Smooth muscle; contration pulls hair follicle upright in response to cold or fear.
  10. Describe the structure of hair follicles.  Is a hair follicle made from epidermis or dermis?
    Hair follicle: folds of epidermal tissue into dermis; base=hair bulb. The hair follicle are made in the dermis.
  11. Describe how hair growth works.
    • Growth stage=cells of matrix differentiate, keratinize and die, hair grows longer.
    • Regressive stage=cells of matrix die,growth of hair stops, hair falls out of follicle (one to three months)
  12. Do haircuts make hair grow faster?  Why?
    No, because it can only be altered by illness, age, gender, genetics, malnutrition, and emotional stress.
  13. What determines hair color and how does this changes with age?
    • Hair color is due to the amount and type of melanin in the cortex and medulla cells of the hair.
    • As we age there is a decline in melanin production; air bubbles replace melanin
  14. Describe the structure of nails and how they grow.  Are nails made from epidermis or dermis?
    • Nails have 3 parts: Free edge, body, root. Nail bed (deeper layer of epidermis) contains nail matix (nail growth)
    • Lunula (white crescent shaped areas) Thickened region of eptihelium underneath, Blood vessels do no show through
  15. Name the two main types of exocrine glands located in the skin.Specifically, where are these glands located (i.e. in what layer)?
    • Eccrine glands: Function is to regulate body temperature. Secrete sweat, and is most abundant on palms, soles of feet, and forehead.(Dermis)
    • Apocrine glands: bacterial breakdown of lipids and proteins lead to musky oder. Open at hair follicles. Secreation is viscous; contain lipids and proteins.(Dermis)

  16. Describe the form and function of the sebaceous glands.
    • Sebum glands accumulate an oily substance until they burst
    • Exocrine glands with holocrine mode of secretion.
    • Secrete sebum into hair follicle or into pore on skin surface
    • Softens and lubricates hair and skin; slows water loss from skin
    • (Found all over the body,except in think skin of palms and soles.
  17. What is acne?
    Inflammation of sebaceous glands on the skin, typically caused by bacterial infection
  18. Name and describe 4 functions of the integumentary system.
    • Protection:Physical,Chemical, and biological barrier.
    • Physical-dead,keratinized cells (abrasion), glycolipids of epidermis (water loss/gain)
    • Chemical barrier- acidic and antiboitic skin secretions(kill microorganisms)
    • Biological barrier-dendri.tic cells in epidermis, macrophages in dermis
    • Body temperature Regulation
    • sweat vasodilation and vasocontriction of dermal blood vessels.
    • Cutaneous sensation:
    • Merkel cells (epidermis)
    • Meissner's corpuscles (dermal papillae of dermis)
    • Lamellar or Pacinian corpuscles (deep dermis or hypodermis)
    • Root hair plexus (hair follicles)
    • Metabloic Functions
    • cholesterol modified to vitamin D precursor
    • Vitamin D important for calcium metabolism
  19. Name and describe the 3 main types of skin cancers.  For each one, in what layer of the skin are cancerous cells found?  What is the most/least dangerous type?
    • Basal cell carcinoma: stratum basale cells proliferate(least dangerous 80% of people have it)
    • Squamous cell carinoma: Second most common, grows rapidly; can metastasize, kerantinocytes from stratum spinosum
    • Melanoma: Most dangerous skin cancer, cancer in the melanocytes can develop from moles
  20. What is and what causes skin burns?
    • Tissue damage inflicted by intense heat,electricity,radiation, or chemicals.
    • Severe burns can lead to loss of body fluids,causing dehydration and electrolyte imbalance
  21. Describe the 3 levels of skin burns.  Which type of burns are the most/least painful?
    • First degree burns: (very painful) Only epidermis is damaged
    • Second degree burns: ( most painful) Damage to the epidermis and upper dermis is done
    • Third degree burns:Full thickness of skin is damage (Not painful at all)
Card Set
Integumentary System.txt
Integumentary system