What does tidal volume (Vt) measure in respiratory physiology?

Tidal volume (Vt) specifically refers to the amount of air that is inhaled or exhaled during normal breathing at rest. It represents the typical volume of air exchanged in a single breath and is a fundamental measurement in respiratory physiology. Understanding tidal volume is crucial because it helps assess lung function and ventilation efficiency in various clinical situations.

The other options do not accurately describe tidal volume: the maximal volume of air inhaled pertains to inspiratory capacity, the total volume of air in the lungs corresponds to total lung capacity, and the volume of air exchanged in one minute relates to minute ventilation. Each of these terms reflects different aspects of respiratory physiology, making it clear that option B correctly defines tidal volume.