Question

Volume of air breathed in or out during normal breathing is called as

• A. Vital capacity
• B. Inspiratory reserve volume
• C. Expiratory reserve volume
• D. Tidal volume

Answer 1

The correct option is D Tidal volume

Volume of air breathed in or out during normal breathing is called as tidal volume. Tidal volume is the lung volume representing the normal volume of air displaced between normal inhalation and exhalation when extra effort is not applied. In a healthy, young human adult, tidal volume is approximately 500 mL per inspiration or 7 mL/kg of body mass.

Vital capacity is the maximum amount of air a person can expel from the lungs after a maximum inhalation. It is equal to the sum of inspiratory reserve volume, tidal volume, and expiratory reserve volume. A person's vital capacity can be measured by a wet or regular spirometer.

The inspiratory reserve volume (IRV), about 3,100 ml, is the additional air that can be forcibly inhaled after the inspiration of a normal tidal volume.

The expiratory reserve volume (ERV), about 1,200 ml, is the additional air that can be forcibly exhaled after the expiration of a normal tidal volume.