| Question | Answer |
| tidal volume | volume inspired or expired with each normal breath |
| inspiratory reserve volume | volume that can be inspired over and above tidal volume |
| expiratory reserve volume | volume that can be expired after the expiration of a tidal volume |
| residual volume | volume that remains in the lungs after maximal expiration |
| anatomic dead space | volume in conductin airways |
| physiologic dead space | functional measurement, volume of the lungs that does not participate in gas exchange |
| minute ventilation | tidal volume X respiration rate |
| alveolar ventillation | ( tidal volume- dead space) X respiration rate |
| Inspiratory capacity | sum of tidal volume and inspiratory reserve volume |
| functional residual capacity | sum of expiratory reserve volume and residual volume; remains in lungs after tidal volume is expired |
| vital capacity | volume of air that can be forcibly expired after maximal inspiration |
| vital capacity | tidal volume + inspiratory reserve volume+ expiratory reserve volume |
| muscels of inspiration | diaphragm and external intercostals |
| muscles of expiration | normally passive, used during exercise; includes abdominal muscles and internal intercostals |
| compliance of respiratory system | distensibility of lungs and chest wall; inversly related to elastance |
| surfactant | reduces surface tension and increases compliance, is produced starting gestational week 24-35 |
| surfactant | synthesized by type II alveolar cells and consits primarily of DPPC; lecithin:sphingomyelin ratio >2:! indicates mature levels of surfactant |
| during rest | alveolar pressure equals atmospheric pressure, intrapleural pressure is negative |
| during inspiration | alveolar pressure becomes negative causing a presure gradient, intrapleural pressure becomes more negative |
| during expiration | alveolar pressure becomes postitive, intrapleural pressure returns to resting value |
