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Secondary bronchi
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Secondary bronchi <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO1_.png)
Secondary bronchi
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Cartilage plates <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO2_-1.png)
Cartilage plates
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Mixed glands <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO3_.png)
Mixed glands
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Pulmonary vessels <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO5_.png)
Pulmonary vessels
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Bronchioles <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO5_-1.png)
Bronchioles
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Alveoli <p>Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.SB_.02.PO6_.png)
Alveoli
Secondary bronchi are intrapulmonary passages that are part of the conducting portion of the respiratory system. As a secondary bronchus branches from a primary, it becomes smaller in diameter and its wall thins. Cartilage plates and mixed glands remain, distinguishing these passages from bronchioles. Pulmonary arteries accompany secondary bronchi. 40x
![Image source > <p>This image was taken from a slide in the University of Michigan slide collection.</p>](https://digitalhistology.org/wp-content/uploads/2019/02/Michigan-source-ping-2.png)
Image source >
This image was taken from a slide in the University of Michigan slide collection.