New York State Emergency Medical Technician (EMT) Practice Exam

What is the term for the amount of air that remains in the lungs to keep them open?

1. Tidal volume

2. Residual volume

3. Inspiratory reserve volume

4. Expiratory reserve volume

The correct answer is: Residual volume

The term for the amount of air that remains in the lungs to keep them open is known as residual volume. This air remains in the lungs after a person exhales and is crucial for maintaining a stable intrapleural pressure, which helps prevent the alveoli from collapsing. Residual volume is important because it ensures that there is always some air in the lungs for gas exchange to occur, even between breaths. This volume helps maintain adequate ventilation and oxygenation in the body. In contrast, tidal volume refers to the amount of air inhaled or exhaled during a normal breath, inspiratory reserve volume is the additional air that can be inhaled after taking a normal breath, and expiratory reserve volume is the additional air that can be forcibly exhaled after a normal exhalation. While these volumes are significant in understanding lung capacity and respiratory function, they do not serve the same purpose as residual volume in keeping the lungs open.