AEMCA Practice Exam

What is functional residual capacity?

1. The volume of air in the lungs after a deep inhale

2. The volume in the lungs at the end-expiratory position

3. The amount of air that can be forcibly exhaled

4. The lung capacity essential for gas exchange

The correct answer is: The volume in the lungs at the end-expiratory position

Functional residual capacity is defined as the volume of air remaining in the lungs after a normal exhalation. This volume is crucial for maintaining a consistent level of oxygen in the blood and ensures that the lungs do not completely empty with each breath. It comprises two components: the expiratory reserve volume (the additional amount of air that can be exhaled after a normal expiration) and the residual volume (the air that remains in the lungs and cannot be exhaled). Understanding this concept is vital for grasping lung function and the mechanics of breathing. The correct answer accurately reflects the state of the lungs at the end of an expiration, highlighting its importance in both the respiratory cycle and overall pulmonary health.