Chapter 5
 Respiratory System - Notes  (Changes and Suggestions in blue and green - 3/6/06)
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 1.  Name and describe the contributions to homeostasis made by the respiratory system's two main functions for homeostasis.

     - gas exchange = obtaining O2 for energy, eliminating CO2 to prevent acidosis and to regulate pH disturbances from any source.
     - sound production = for communication

 2.  Explain the need for adaptability in gas exchange.

     - must
or gas exchange to maintain O2, CO2, and pH homeostasis as body activity or or other factors disturb O2, CO2, or pH.

 3.  Name and describe the three processes involved in gas exchange. (pp. 95-96)

    (1) ventilation (air exchange = breathing)
    (2) perfusion (pulmonary blood flow) (pp. 69, 102, 106)
    (3) diffusion (alveolar exchange of O2 and CO2) (pp. 102, 106)

 4.  Name and briefly describe each of the two parts of ventilation. (pp. 95, 97)

     - (1) inspiration is active using the diaphragm (more efficient) and or other muscles like the external intercostals (less efficient) to increase volume and decrease pressure
     - (2) expiration is normally passive from elastic recoil of the thorax and abdomen, but may be active using muscles (internal intercostals, abdominal)

5.  Describe work of breathing and explain its significance relative to the goals of the respiratory system.

     - work of breathing = amount of O2 used for ventilation
   
        - usually less than 5% of total O2 brought in by the respiratory system
     - work of breathing consumes some of the O2 brought in by the system, leaving the remainder for use by the body      
   
        - work of breathing leaves less O2 for the remainder of the body
     - work of breathing produces CO2, requiring that the respiratory system eliminated this CO2 as well as that produced by the rest of the body
   
        - work of breathing means more CO2 must be removed to prevent CO2 build-up
     - work of breathing  acts counter to the goals of the respiratory system

 6.  Compare and contrast the mechanisms and outcomes from quiet ventilation (quiet breathing) and forced ventilation (forced breathing).

     - quiet ventilation moves less air at slower rates = less minute volume than forced ventilation (See objectives above for details).
     - also, quiet respiration is passive, while forced expiration is active and uses more O2 and produces more CO2

 7.  Explain how the rate of ventilation is determined.

     - rate of ventilation = minute volume = volume per breath x breaths/minute

 8.  Name and define total lung capacity and the parts thereof plus dead space. (p. 105)

     - total lung capacity = tidal volume + inspiratory reserve capacity + expiratory reserve capacity + residual volume
     - dead space = volume in airways

 9.  Name and explain the importance of the five requirements for proper ventilation.

- (1) open airways (p. 94), (2) defense mechanisms (pp. 99, 100), (3) proper pressure changes (p. 97), (4) compliance, (5) control systems (p. 99)

10.  Name two age changes that affect each of the five requirements for proper ventilation, describe the results of these age changes on ventilation, and describe the results of these changes on (1) maximum minute volume, (2) maximum rate of gas exchange, (3) maximum rate of providing O2 and removing CO2 for body cells, and (4) work of breathing.

(1) open airways
       (1) mucous has
viscosity plus
       (2) cilia have
number and rate of movement -> clearance -> narrower airways -> max. minute volume and work of breathing -> maximum rate of gas exchange and O2 and CO2 servicing
       (3) narrowing smaller airways ->
maximum minute volume plus work of breathing plus residual volume ( closing volume) -> maximum rate of gas exchange and O2 and CO2 servicing
       (4) widening larger airways ->
dead space -> stale air in lungs -> rate of diffusion -> maximum rate of gas exchange and O2 and CO2 servicing (Note that age-related TV helps compensate for residual volume

(2) defense mechanisms
       (1)
defense mechanisms (mucociliary clearance; swallow, gag, cough; ?phagocytosis?; immune function) -> risk of respiratory blockage, injury, and infection -> risk of limited respiratory functioning

(3) proper pressure changes
       (1) weaker muscles ->
maximum minute volume
       (2) stiffer skeletal elements plus
       (3) altered chest shape and posture ->
maximum pressure changes -> maximum minute volume plus work of breathing (partial compensation by diaphragmatic breathing)
       (4) limper lungs (altered collagen helices) ->
recoil -> maximum minute volume plus work of breathing
       (5) shallower alveoli (p. 104)->
surface area -> surface tension -> recoil - maximum minute volume plus work of breathing
- all changes-> 
maximum rate of gas exchange and O2 and CO2 servicing

(4) compliance
       (1) limp collagen helices ->
lung compliance
       (2)
stiffness of all other parts overrides lung compliance -> overall respiratory stiffness -> maximum rate and amount of inspiration -> maximum minute volume and work of breathing -> maximum rate of gas exchange and O2 and CO2 servicing

(5) control systems
       (1)
sensitivity of neurons (respiratory center, aorta, carotids, ?muscle and joints?)  -> detection of altered O2, CO2, and pH -> adaptation
       (2) ?decline in neuron pathways? -> reduced control
       (3)
lung sensitivity to norepinephrine -> responsiveness

(1) + (2) + (3) ->
speed and degree of adaptation - more rapid dyspnea on exertion

Overall results include
maximum flow rate, volume/breath, maximum breathing rate (breaths/minute) -> maximum minute volume plus work of breathing -> maximum rate of useful gas exchange

11.  Describe age changes in lung volumes and the effects of these changes on the ability of the respiratory system to carry out its functions. (p. 105)

- decreases in TLC, IR, and ER with increases in RV and dead space (and slight increase in TV) cause decrease in maximum minute volume and decrease in efficiency due to mixing a lower amount of fresh air with a higher volume of stale air. All these changes cause decrease in rate of diffusion and therefore decrease maximum rate of activity.

12.  Describe the overall effects of age changes altering ventilation on a person's ability to carry out activities of different intensities.

- age changes affecting ventilation are not important during light or moderate rates of activity

13.  Describe the overall effects of age changes in pulmonary vessels (perfusion) on gas exchange.

     - little or no effect except possibly a decline in maximum rate of perfusion and maximum rate of gas exchange

14.  Name the three requirements for effective diffusion.

     - large, thin, moist surface area

15.  Describe the two age changes in alveoli and indicate their effect on diffusion. (p. 104)

     - flatter (shallower) and thicker -> decline in maximum rate of diffusion

16.  Name the two overall effects of age changes in the respiratory system on its ability to provide homeostasis for O2 and CO2 and pH.

     - lower maximum rate of gas exchange plus decreased efficiency from increased work of breathing -> decline in maximum rate of work
     - decreased rate and amount of adaptability of respiratory system -> faster dyspnea on exertion
     - note: retention of adequate respiratory functioning for light or moderate activity levels

17.  Describe the effects of amounts of exercise and levels of health on age changes affecting ventilation.

     - exercise and good health minimizes rate and degree of age changes
     - lack of exercise and poor health increase rate and degree of age changes

18.  Describe non-biological effects from age changes in the respiratory system related to biological age changes in respiration.

     - select specific examples of social, psychological, and economic effects and interactions with biological and the other types of effects

19.  Name several types of air pollution and explain why reducing exposure to air pollution is important.

     - smoking, occupational air pollution (fibers, coal, sawdust, asbestos, exhaust fumes, solvent fumes), urban air pollution, farm air pollution
     - air pollution increases the adverse effects of aging on respiration, leading to decreased maximum speed and endurance, disability, disease, and death

20.  Name four reasons for the increased incidence and severity of respiratory system diseases as age increases.

     - (1) increased risk and incidences of exposure to factors, (2) increased duration of exposure to factors, (3) lowered body defenses, (4) more time for slow diseases to develop

21.  Name ways (one for each) that lung cancer reduces each of the three processes in respiration (ventilation, perfusion, and diffusion).

     - ventilation; narrower airways, pressure on lungs, fill alveoli
     - perfusion; distorts, compresses, and reduces blood vessels (hemorrhaging)
     - diffusion; thickens alveolar walls, replaces alveolar walls

22.  For either chronic bronchitis, emphysema or pneumonia, explain three ways that the one you choose reduces respiratory functioning.

     - chronic bronchitis: produces mucous (narrows airways), cilia and ciliary action ( clearance and risk of infection), swelling of airways (narrowness -> ventilation, especially expiration), coughing ( work of breathing)
     - CLE -> collapsing airways -> residual air and work of breathing and blood vessels -> perfusion (and CHF)
     - PLE -> elimination of alveoli -> ventilation ( elasticity and surface tension and residual air) and work of breathing, perfusion ( blood vessels and CHF, diffusion ( surface area)
     - pneumonia; bacterial -> filled airways and possible death of lung tissue: viral -> thicker respiratory membranes: fungi and TB -> death of lung tissue: Dusts and vapors -> pulmonary fibrosis -> lung stiffness (and vessels and thicker respiratory membranes)
     - blebs -> pneumothorax -> decrease inspiration -> decreased ventilation

23.  Describe non-biological effects from age changes in the respiratory system related to diseases of the respiratory system.

     - select specific examples of social, psychological, and economic effects and interactions with biological and the other types of effects

24.  List four adverse effects from smoking including three from outside the respiratory system.

     - free radical formation; decreasing antioxidants; amplifies age changes and incidences of diseases in skin; increases risks of high blood pressure, blood clots, and atherosclerosis; increases incidence of cataracts; increases risks of osteoporosis; increases risk of diabetes mellitus; decreases immune system functioning; increases risk of many cancers.

25.  Name two adverse effects either from snoring or from age changes in vocalization.

     - snoring: (1) blood pressure, (2) O2 and CO2, (3) overworks heart, (4) disrupts sleep, (5) disturbs others, (6) social, psychological, and economic side effect
     -vocalization: (1) control of volume and pitch, (2) control of word formation -> difficulty being understood, (3) volume; all changes -> social and psychological impact.

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