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* Histo Questions - 5
 #144255  
  drbilan - 12/08/06 11:13
 
  Which of the following statements is CORRECT?

A. During a shallow tidal inspiration, the respiratory muscles must overcome the elastic recoil of the lungs and the chest wall.
B.At FRC, the elastic recoil pressure generated by the lungs (i.e. trans-pulmonary pressure) is zero.
C. The elastic equilibrium point of the chest wall (i.e. when the pressure gradient across the chest wall is zero) occurs at approximately 60% of the vital capacity.
D. To reach RV, the respiratory muscles must overcome the elastic recoil of both the lungs and the chest wall.
 
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* Re:Histo Questions - 5
#582757
  sharky - 12/08/06 11:21
 
  b.,.?  
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* Re:Histo Questions - 5
#582775
  paganini - 12/08/06 11:31
 
  I think is B  
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* Re:Histo Questions - 5
#582776
  capsule - 12/08/06 11:31
 
  b.  
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* Re:Histo Questions - 5
#582806
  drbilan - 12/08/06 11:56
 
  try again.....  
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* Re:Histo Questions - 5
#582821
  ar513 - 12/08/06 12:12
 
  I think its A  
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* Re:Histo Questions - 5
#582823
  paganini - 12/08/06 12:13
 
  Well is not C because it occurs at 25% of vital capacity, regarding B the elastic recoil generated by the lung is a positive pressure not zero, I know understand, but is opposite and equal to chess wall pressure so they are equally balnaced. Now I have to chose between A and D, I will go with A, during inspiration (inflation) you should overcome the elastic recoil.

Ans: A
 
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* Re:Histo Questions - 5
#582828
  drbilan - 12/08/06 12:17
 
  try again
 
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* Re:Histo Questions - 5
#582832
  drbilan - 12/08/06 12:20
 
  The reason that the answer is not A is:
At end-expiration (FRC), the recoil of the chest wall is outward. This recoil actually helps the diaphragm expand the lungs during a tidal breath.
 
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* Re:Histo Questions - 5
#582833
  paganini - 12/08/06 12:20
 
  If is not A is D. Now iI am guessing, please give the explanation  
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* Re:Histo Questions - 5
#582857
  drbilan - 12/08/06 12:40
 
  The answer si C
Dr. paganini it occurs at 60% of vital capacity.
 
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