![This is blank.](https://digitalhistology.org/wp-content/themes/histology-unified/imgs/trans.png)
Pulmonary artery
This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x
![Passageway <p>This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PA_.02.P01.png)
Passageway
This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x
![Pulmonary artery <p>This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PA_.02.P02.png)
Pulmonary artery
This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x
![Alveoli <p>This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.B.PA_.02.P03.png)
Alveoli
This terminal bronchiole transitioning to a respiratory bronchiole is accompanied by a branch of the pulmonary artery. This vessel is located adjacent to the passageway rather than being located within the wall of the passage as a bronchial vessel would be. 150x