The following questions represent a review of respiratory physiology.  They are taken from the class syllabus from my actual freshman year.  If some of this information seems a little dim and high-school like, that's because you probably learned it in high school.  Let me assure you though, it was reviewed in veterinary school.

QUESTIONS

1. What in the hell is dipalmitoyl lecithin?
    
2. What is Boyle's Law?
    
3. What is Charles' Law?
    
4. What is Absolute Zero in Centigrade & how is it defined?
    
5. What is Dalton's Law?
   
6. What kind of epithelium do you have in an alveolus?
    
7. What is Fick's Law?
    
8. When a CO2 molecule happily diffuses out of a cell, there are three things that can happen to it.  What are they?
    
9. What is the Haldane Effect?
    
10. In hemoglobin, how many O2's bind to each iron?
     
11. What is the Bohr effect?
     
12. What is the isohydric shift?
     
13. Wht is the effect of increased body temperature on the oxygen dissociation curve of hemoglobin?
    
14. 2,3 DPG is a by-product of glycolysis.  It is very plentiful in rbc's.  What does it do which might explain why its levels rise in high altitudes?
    
    
    
    
     

ANSWERS

1. Dipalmitoyl lecithin is the major ingredient of pulmonary surfactant (The stuff that keeps one's alveoli from closing up on exhalation).
   
   
   
   
    
2. Boyle's law says that at a constant temperature, the volume of any gas varies inversely with pressure.  In other words if you change from pressure 1 & volume 1 to pressure 2 & volume 2 without changing temperature:  P1V1 = P2V2.
   
   
   
   
    
3. Charles' Law says that the volume of a gas at a constant pressure increases proportionately with the temperature.   So if you have a mass of gas at 2 temps & 2 volumes:
                                                                             V1                T1
                                                                         --------    =    --------
                                                                             V2                T2
   
   
   
   
    
4. Absolute zero is -273 degrees centigrade (=0 degrees Kelvin).  This is the temp at which molecular motion ceases.
   
   
   
   
    
5. Dalton's Law says that the partial pressures of each type of gas in a mixture add up to get the total pressure.
   
   You have squamous epithelium in your alveoli.
   
   
   
   
    
6. In diffusion, a solute moves from an area of high concentraion to areas of low concentration according to Fick's Law of Diffusion.
   
   
   
   
    
7. Change in quantity of solute in an area over change in time = D x Area through which diffusion is occuring x concentration gradient where D = a coefficient determined by properties of the solute & solution.
   
   In the English language, the diffusion of O2 & CO2 between interstitial fluid & capillary blood is determined by Fick's law.  Area relates to capillary density (more surface area for diffusion).
   
   
   
   
    
8. 8% combines with H2O to become carbonic acid & then bicarb in the plasma.  This happens right there in the plasma with out the CO2 molecule entering a red cell.  Or, the C02 molecule can enter a red cell.  65% of CO2 turns into bicarb/carbonic acid via carbonic anhydrase within the red cell.  27% of CO2 reacts with hemoglobin to create carbaminohemoglobin.
   
   
   
   
    
9. This effect refers tot heeffect of O2 on Co2 transport.  In high oxygen tension (lungs) CO2 tends to come off hemoglobin while in low oxygen tension, it wants has higher affinity for hemoglobin.
   
   
   
   
    
10. One O2 per iron.  There are 4 irons in one hemoglobin.  (As you know, oxygen affintiy increases with each oxygen bound except the 4th oxygen seems to have less affinity.  Hence, the sigmoidal shape of the oxygen dissociation curve.)
    
    
    
    
     
11. Hemoglobinis a weaker acid than oxyhemoglobin.  This means that Hb binds H+ more readily than oxyHb.  A lower pH (more CO2)  causes a right shift in the oxygen dissociation curve.  This means that when pCO2 is high, Hb gives up oxygen easier. 
    
    
    
    
     
12. The isohydric shift refers to the fact that Hb is an effective buffer.  CO2 can be taken up by Hb without a pH change.
    
    
    
    
     
13. Increased body temp causes a right shift in the curve (oxygen is released easier).
    
    
    
    
     
14. 2,3 DPG stabilzes the deoxygenated form of hemoglobin.  It helps oxygen get released to tissues.  Since, in higher altitudes there is less oxygen to breathe, you need all the help you can get getting O2 to your cells.