By spirometry, one can measure -

Ans. is 'd' i.e., Tidal volume o Pulmonary ventilation can be studied by recording the volume movement of air into and out of the lungs, a method called spirometry.o A spirometer is a device in which, one breathes into and out of the device.o The volume of air breathed in or out are measured.o Spirometry can measure (spirometric measurement are) : - Tidal volume (TV), inspiratory reserve volume (IRV), expiratory reserve volume (ERV), and vital capacity (VC)r /FEV1.o As residual air (residual volme) can not be expired (residual volume is the amount of air remaining in the lung after maximum possible expiration), residual volume cannot be measured by spirometry ,o Therefore, the capacities which have residual volume as one of their components, cannot be measured by spirometry.o These capacities are functional residual capacity (ERV + RV) and total lung capacity (VC + RC).o The commonly employed methods for functional residual capacity (FRC) estimation are: -i) Gas-dilution methods : - Helium dilution technique, nitrogen washout technique.ii) Plethysmography