<prompt> Vital capacity is sum ofInspiratory reserve volume, Tidal volume and Expiratory reserve volumeTidal volume, Inspiratory reserve volume and Residual volumeExpiratory reserve volume, Inspiratory reserve volume and Residual volume.Residual volume, Inspiratory volume, and Expiratory reserve volume.  <response>: Ans. a Inspiratory reserve volume, Tidal volume and expiratory reserve volume Ref Ganong 23rd593Ganong 23rdFig. 35-7: VC 4700 ml ERV TV IRVRespiratory volumes and capacities for an average young male.MeasurementTypicalDefinitionRespiratory volumes1Tidal volume TV500 mlAmount of air inhaled or exhaled in one breath during relaxed quiet breathing2Inspiratory reserve volume IRV3000 mlAmount of air in excess of tidal inspiration that can be inhaled with maximum effort3Expiratory reserve volume ERV1200 mlAmount of air in excess of tidal expiration that can be exhaled with maximum effort4Residual volume RV1200 mlAmount of air remaining in the lungs after maximum expiration; keeps alveoli inflated between breaths and mixes with fresh air on next inspirationRespiratory Capacities5Vital capacity VC4700 mlAmount of air that can be exhaled with maximum effort after maximum inspiration ERV TV IRV; used to assess strength of thracic muscles as well as pulmonary function6Inspiratory capacity 1C3500 mlMaximum amount of air that can be inhaled after a normal tidal expiration TV IRV7Functional residual capacity FRC 2400 mlAmount of air remaining in the lungs after a normal tidal expiration RV ERV8Total lung capacity TLC5900 mlMaximum amount of air the lungs can contain RV VCAdditional Educational points In a healthy normal adult male, FVC is approximately 5.0 L, FEV, is approximately 4.0 L, and thus, the calculated FEV1 FVC is 80. Obstructive disorders result in a marked decrease in both FVC and FEV1FVC, whereas restrictive disorders result in a loss of FVC without loss in FEV1FVC. FEV1FVC for obstructive 42 versus restrictive 90 patients defines the hallmark measurements in evaluating these two diseases. 