breathing and exchange Flashcards
Tidal volume(TV)
Volume of air inspired or expired during a normal respiration, approx 500 mL i.e., 6000 to 8000 mL per min
Inspiratory reserve volume(IRV)
additional volume of air a person can inspire by a forcible inspiration; 2500-3000 mL
ERV
additional volume of air a person can expire by a forcible expiration; 1000-1100 mL
Residual Volume(RV)
volume of air remaining in the lungs even after a forcible expiration. This averages 1100 mL to 1200 mL.
Inspiratory Capacity(IC)
total volume of air a person can inspire after a normal expiration. This includes tidal volume and inspiratory reserve volume TV+IRV 3000-3500 mL
EC
total volume of air a person can expire after a normal inspiration. TV+ERV; 1500-1600 mL
Functional residual capacity (FRC)
Volume of air that will remain in the lungs after a normal expiration. ERV+RV; 2100-2300 mL
Vital Capacity (VC)
the maximum volume of air a person can breathe in after a forced expiration or the max vol of air a person can breathe out after a forced inspiration. ERV+TV+IRV=3000-4500 mL.
Total Lung Capacity (TLC):
total vol of air accomodated in the lungs at the end of a forced inspiration TV+ERV+IRV+RV or VC+RV; 5000-6000 mL.
3 layers of alveoli involved in diffusion
- thin squamous epithelium of the alveoli
- endothelium of the alveolar capillaries
- basement substance in between them
where does gas exhanmge take place?
- b/w alveoli and blood
-b/w blood and tissues
factors affecting rate of diffusion
- concentration gradient/pressure gradient
-solubility of gases
-thickness of membrane involved
factors affecting oxygen association curve
low pO2, High pO2, low temp, low H+ conc
total thickness of alveolar membrane
nearly 1 mm
