The boundary between conducting zone and respiratory zone structures occurs at the

The boundary between conducting zone and respiratory zone structures occurs at the terminal bronchiole/respiratory bronchiole junction. The major respiratory structures span the nasal cavity to the diaphragm. Functionally, the respiratory system can be divided into a conducting zone and a respiratory zone. The conducting zone of the respiratory system includes the organs and structures not directly involved in gas exchange. The gas exchange occurs in the respiratory zone.