Physiology of Breathing

Card Set Information

Physiology of Breathing
2013-02-27 21:24:18
BIO 220 Test Two

Show Answers:

  1. Ventilation: __
    __ phases
    • breathing
    • two: inhalation/ exhalation
  2. Explan Inhalation
    • 1.      breathing in (inspiration)
    • a.      Active; requires energy; muscle contractions in the intercostals muscles (between ribs) and diaphragm (Separates thoracic)
    •                                                                                                                                       i.      Must contract to get water in, increasing size of thorax, and therefore, the lungs
  3. Explain exhalation.
    • 1.      breathing out (expiration)
    • a.      Passive; normal recoil of muscles
    •                                                                                                                                       i.      They go back and air comes out
  4. Transport of the Respiratory gases occurs by __.
    circulatory system
  5. How is oxygen transported?
    •                                                               i.      If you look at normal arterial blood, most of the oxygen (osver 98.5% percent) is transported by hemoglobin
    •                                                             ii.      1.5% is dissolved oxygen in plasma; majority is in red blood cell being transported by hemoglobin
  6.                                                               i.      Oxygenated blood= __
    1.      Attached to __group, specifically, the __of the __group
    • oxyhemoglobin
    • heme
    • iron
    • heme
  7.                                                               i.      If every hemoglobin molecule had four oxygen attached to it, your blood will be __
    100% saturated
  8. 1.      Factors that affect this percentage and how much oxygen attaches to hemoglobin
    • the partial pressure of oxygen
    •                                                                                                                                       i.      Increased amounts of Carbon dioxide
    • Temperature 
  9. Explain partial pressure of oxygen
                                                                                                                                          i.      The greater the PO2, the greater the percent of oxyhemoglobin (with increase in PO2, % saturation increases until you reach one hundred percent)
  10. Increased amounts of Carbon dioxide
    • 1.      When CO2 is in circulatory system, it combines with water and forms carbonic acid, which forms the hydrogen ion and the bicarbonate ion
    • 2.      High carbon dioxide or low PH (acid) is going to affect the amount of saturation
    • a.      High PCo2 (high acid; low pH) is going to cause less saturation and oxygen to be released from hemoglobin BECAUSE THE TISSUES WANT IT 
  11. What does high PCO2 result in?
    •                                                                                                                                                                                                               i.      Results in decreased saturation of hemoglobin because the hemoglobin is releasing oxygen
    •                                                                                                                                                                                                             ii.      Hemoglobin releases oxygen because of the Bohr effect, which is the hydrogen ions (that came from the carbon dioxide dissociating with water combining with hemoglobin) cause a conformational change in the hemoglobin molecule such that it releases oxygen; hydrogen ions attached to hemoglobin cause conformational change that causes release
    •                                                                                                                                                                                                           iii.      Bohr effect is a RESULT of high CO­2, low PH, and high acid
  12. Where is High PO2 located?
                                                                                                                                                                                                                  i.      High PO2 is going to be highest in lungs; the more the tissues are creating CO2, the more they want oxygen; so, the Bohr effect causes oxygen to be released
  13. Explain temperature
    • 1.      Within normal limits, an increase in temperature favors dissociation (oxygen release from hemoglobin)
    • 2.      Less saturation at higher temperatures
    • a.      If oxygen is coming off, then it is less saturated
    • b.      Examples of high temperature is when the metabolically active cells are releasing a lot of heatà wants more oxygen; favors dissociation
  14. Carbon dioxide
    •                                                               i.      Unlike Oxygen (98.5% carried by hemoglobin), carbon dioxide is carried in three ways
    • 1.      10% dissolved blood
    • 2.      30% attached to hemoglobin (Carb-amino hemoglobin; attaches to globin portion, not heme; it does not compete with oxygen)
    • 3.      60% as bicarbonate ions (will combine with water and form carbonic acid, which dissociates into bicarbonate and hydrogen ion)
  15. What don't want to do?
    •                                                               i.      We don’t want to dump a lot of ions in the plasma and have osmotic pressure
    • 1.      So, for every bicarbonate that leaves, a chloride ion enters the red blood cell to prevent ionic imbalance
    • a.      CHLORIDE SHIFT