Question

Approximately ____ mL of air remains in the anatomic dead space of an adult with a tidal volume of 500 mL?

1) 100
2) 125
3) 150
4) 175

Answer 1

Approximately 150 mL of air remains in the anatomic dead space of an adult with a tidal volume of 500 mL, as it doesn't reach the alveoli for gas exchange.

Step-by-step explanation:

The anatomic dead space in an adult refers to the volume of air that remains in the respiratory passages where gas exchange does not take place. This dead space typically measures approximately 150 mL in a healthy adult. When an adult with a tidal volume of 500 mL takes a normal breath, this is the amount of air that occupies the mouth, nose, trachea, and bronchi and does not reach the alveoli where gas exchange occurs.

Therefore, of the 500 mL of air inhaled, approximately 150 mL remains in the anatomic dead space, with the remaining 350 mL reaching the alveoli and participating in gas exchange.