Chapters 3
 Integumentary System - Notes (Changes and Suggestions in blue and green - 3/6/06)
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 1. Name and explain the importance of the four (five) ways the integumentary system helps maintain homeostasis.

      (1) barrier - against (1) microbes (infection), (2) chemicals (external ones harmful to cells, internal ones helpful to cells), (3) water (balance necessary for cells), (4) light (harmful to protein fibers, cell proteins, DNA), (5) trauma (promotes infection, allows leakage of desirable substances, damage to cells)

      (2) provide information - monitoring for (1) negative and positive feedback, (2) pleasure

      (3) temperature regulation - (1) maintain warmth (-> proper rate of reactions, comfort) (2) prevent overheating (-> damage to molecules, discomfort) or coolness (-> slow reactions, discomfort)

      (4) vitamin D production - for calcium absorption by intestine

      (5) defense - actively protecting the body from harmful physical and biological factors

 2. Name five types of factors for which the integumentary system is a barrier and explain the importance of each.

      (1) microbes (infection)
      (2) chemicals (external ones harmful to cells, internal ones helpful to cells)
      (3) water (balance necessary for cells)
      (4) light (harmful to protein fibers, cell proteins, DNA; promotes free radical production )
      (5) trauma (promotes infection, allows leakage of desirable substances, damage to cells)

 3. Name the functions of keratin, melanin, and Langerhans cells, describe the effects of aging on these functions, and explain the importance of these age changes with regard to homeostasis and appearance (where applicable).

      - keratin -> barrier to microbes, chemicals, water, trauma
           AGING -> (1) slightly thinner and uneven -> decr. barrier (chemicals)
             (2) weaker and looser -> decr. barrier (microbes, chemicals), scaly appearance
             (3) slower production -> slower healing -> decr. barrier (microbes, water, chemicals, trauma)
     - melanin -> barrier to light
           AGING -> (1) less, slower production -> decr. barrier to light -> incr. sunburn, incr. skin cancer, incr. wrinkling, decr. immune response
                 (2) uneven distribution -> cosmetic problems ("age spots")

      - Langerhans cells -> barrier (start immune responses against microbes, chemicals), fights skin cancer
           AGING -> (1) decreased numbers -> decr. immune response -> decr. allergic responses (decr. discomfort, decr. warning of danger {microbes, chemicals} and  decr. defense (microbes, chemicals, cancer)

 4. Name and describe two age changes in hair or nails (you select your favorites) and explain the importance of the changes you select.

      - hair -> shade, thermal insulation, cushion, filter, incr. touch sensation
           AGING -> fewer; thinner; rougher; decr. color; altered distribution (  -> incr. in hair on face, chin, lips;   -> baldness, incr. in eyebrows, ears, nostrils) -> decr. most functions in most areas {some exceptions} and altered cosmetic effect {mostly worse effect}

      - nails -> protect from trauma; used as "tools"
           AGING -> weaker, slower growth, less clear, rougher -> decr. protection, worse cosmetic effect, incr. nail infections

 5. Describe two examples (not found in the text) of social, psychological, or economic effects from age changes in hair or nails.

      (BE CREATIVE AND IMAGINATIVE)

 6. The integumentary system contributes to homeostasis in four main ways. By using two specific examples for each of the four ways, describe how age changes in the dermis alter the integumentary system's ability to contribute to homeostasis.

     barrier

      1. cross-linked collagen -> stiffness - incr. traumatic injury
      2. enzymes weaken collagen -> incr. traumatic injury
      3. decr. fibroblast functioning -> slower healing
      4. decr. WBCs and decr. macrophages -> decr. immune response
      5. decr. vessels -> decr. inflammation
      6. decr. vessels -> weaker skin and slower healing

     information

      1. decr. WBCs, macrophages, mast cells -> decr. immune response, decr. inflammation
      2. decr. vessels -> decr. inflammation
      3. decr. touch and pressure receptors -> decr. sensation

     temperature regulation

      1. decr. vessels and slower vessel response -> decr. temp. regulation (for heat & cold)
      2. decr. sweat glands and sweat gland functioning -> decr. temp. regulation (for heat)

     Vitamin D production

      1. slower cells and reactions -> decr. vitamin D production
      2. decr. water and incr. fiber cross-links -> trapped vit. D
      3. decr. vessels -> decr. supply of raw materials and decr. removal of vit. D

    Defense

      1. decr. WBCs, macrophages, mast cells -> decr. immune response, decr. inflammation
      2. decr. vessels -> decr. inflammation

 7. Describe three age changes in the dermis that have cosmetic effects, and explain the cosmetic effects that result from each change you describe.

      (1) incr. irregularity and binding of elastin -> sagging, wrinkling
      (2) decr. water -> sagging, wrinkling
      (3) decr. vessels -> paleness
      (4) decr. sebum production -> incr. roughness of skin and decr. luster of hair

 8. Name two age changes in the boundary between the epidermis and the dermis, and explain two effects from these age changes.

      (1) decr. number of connections by keratinocytes
      (2) decr. number and size of dermal papillae
      EFFECTS = decr. service of epidermis, incr. separation of epidermis and dermis -> decr. healing, incr. pain, incr. infection, decr. gripping by fingerprints

 9. Explain how age changes in the subcutaneous layer affect its contributions to (1) protecting the body from trauma and (2) maintaining normal body temperature.

      (1) thinning fat, decr. water in gel -> decr. cushioning -> incr. injury from trauma
      (2) thinning fat -> decr. insulation -> decr. temp. regulation

10. Describe three practical applications of your knowledge about age changes in the dermis and subcutaneous layers that are not mentioned in the text.

     (BE CREATIVE AND IMAGINATIVE)

11. Describe the overall age-related trends (e.g., occurrence, severity) in integumentary system abnormalities and diseases.

      - incr. occurrence and incr. severity with incr. age

12. Name four effects from long term chronic exposure of the skin to sunlight.

     - increased production of and damage from free radicals
     - incr. production of irregular keratinocytes -> incr. skin cancer
     - incr. patchy distribution of melanocytes -> incr. "age spots"
     - decr. Langerhans cells -> incr. infection, incr. skin cancer, decr. warning from inflammation
     - incr. irregularities in elastin -> incr. sagging and wrinkling
     - decr. blood vessels -> decr. inflammation for warning, decr. temp. regulation, decr. vit. D production and removal
     - thicker capillary walls -> decr. exchange for epidermis, dermis, Vit. D production and removal
     - enlarged sebaceous glands -> adverse cosmetic effects (i.e., blackheads)

13. Name four ways to reduce or prevent effects from long term chronic exposure of the skin to sunlight.

     - avoid exposure
     - wear protective clothing
     - use sun screen lotions
     - use anti-oxidant lotions

14. List and describe benefits from using tretinoin.

     - reduce sun damage
     - revere cosmetic effects from sun damage
     - reverse sun damage to collagen, vessels, and the junction between the epidermis and dermis

15. Name four effects from long term chronic exposure of the skin to heat.

     - incr. production of irregular keratinocytes -> incr. skin cancer
     - incr. patchy distribution of melanocytes -> incr. "age spots"
     - decr. Langerhans cells -> incr. infection, incr. skin cancer, decr. warning from inflammation
     - decr. blood vessels -> decr. inflammation for warning, decr. temp. regulation, decr. vit. D production and removal
     - thicker capillary walls -> decr. exchange for epidermis, dermis, Vit. D production and removal
     - enlarged sebaceous glands -> adverse cosmetic effects (i.e., blackheads)

16. Name three factors that increase the risk of developing decubitus ulcers as age increases.

      - incr. immobility; age changes weaken skin; thinner fat layer; circulatory diseases (e.g., atherosclerosis); decr. nutrition; decr. skin hygiene; decr. exercise; incr. diseases (e.g., atherosclerosis, diabetes)

17. Name two adverse effects from decubitus ulcers.

      - infection; pain; adverse cosmetic effect

18. Describe the feature that distinguishes benign neoplasia from malignant neoplasia (cancer).

      - benign does not spread to other parts of body
      - malignant spreads to other parts of the body

19. Name two adverse effects from benign skin neoplasia.

      - cosmetic; incr. risk of skin injury; discomfort; incr. risk of infection

20. Name two adverse effects from malignant skin neoplasia.

      - cosmetic; infection; damage other organs

21. Name three ways to prevent the development of integumentary system abnormalities and diseases.

     - skin care; decr. sunlight; remain active; good nutrition; regular evaluation and corrective measures; decr. exposure to harmful factors (microbes, trauma, burns, chemicals); avoid or treat other diseases (e.g., atherosclerosis, diabetes)

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