Biological Systems MCAT Practice Exam

What term describes the additional air that can be forcibly inhaled after a normal tidal volume?

1. Expiratory reserve volume

2. Inspiratory reserve volume

3. Residual volume

4. Functional residual capacity

The correct answer is: Inspiratory reserve volume

The term that describes the additional air that can be forcibly inhaled after a normal tidal volume is known as inspiratory reserve volume. This volume represents the capacity of the lungs to take in more air than what is typically breathed in during a normal, relaxed breath, which is referred to as tidal volume. When you take a deep breath in after a normal inhale, the extra air you draw in is the inspiratory reserve volume. This is particularly important in various physiological contexts, such as exercise or when the body needs more oxygen. Understanding this concept helps to comprehend lung function and respiratory mechanics, which are crucial in fields like physiology and medicine. The other terms relate to different components of lung capacity: expiratory reserve volume refers to the amount of air that can be forcibly exhaled after a normal exhalation, residual volume is the air that remains in the lungs after forced exhalation, and functional residual capacity is the total amount of air remaining in the lungs after a normal exhalation. Each of these has distinct definitions and implications in respiratory physiology.