What is the inspiratory capacity after normal expiration?

Inspiratory capacity is defined as the maximum amount of air that can be inhaled after a normal expiration. It is the sum of tidal volume (the amount of air inhaled or exhaled during a normal breath) and inspiratory reserve volume (the additional air that can be inhaled after taking a normal breath).

In an average adult male, the inspiratory capacity typically ranges around 3600 mL. This value combines the average tidal volume (about 500 mL) and the average inspiratory reserve volume (around 3100 mL). Thus, when the normal expiration is completed, an individual can inspire up to 3600 mL of air, making it the correct answer.

Understanding the concept of inspiratory capacity helps in grasping the functionality of the respiratory system, particularly how much additional air the lungs can hold after normal breathing. This knowledge can be critical in clinical settings, especially when assessing patients' lung function and overall respiratory health.