![This is blank.](https://digitalhistology.org/wp-content/themes/histology-unified/imgs/trans.png)
Bronchiole
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Bronchiole <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P01-1.png)
Bronchiole
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Epithelium <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P02-1.png)
Epithelium
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Smooth muscle <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P03.png)
Smooth muscle
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Bronchial blood vessels <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P04.png)
Bronchial blood vessels
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Alveoli <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P05.png)
Alveoli
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x
![Lymphoid nodule <p>This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x</p>](https://digitalhistology.org/wp-content/uploads/2018/06/O.R.I.C.B.04.P06.png)
Lymphoid nodule
This smaller bronchiole is still lined by a pseudostratified columnar epithelium with cilia. The contraction of the thick smooth muscle layer produced the folding typical of this passageway; this muscle reaches its greatest relative thickness in the bronchiole. No cartilage nor mixed glands are present. 100x