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The histological component that is characteristic of bronchioles is smooth muscle and the absence of glands or cartilage. As the airway transitions from larger bronchi to the smaller bronchioles, there is a gradual decrease in the number of goblet cells and mucous glands. In bronchioles, smooth muscle becomes more prominent, allowing for the regulation of airway diameter and airflow, which is crucial for efficient ventilation.

The absence of cartilage is also a key feature, as bronchioles do not possess the C-shaped cartilage rings found in larger bronchi. Instead, they rely on the supportive structure provided by the surrounding lung parenchyma and the elastic fibers that enable flexibility and compliance.

The presence of significant goblet cells is more typical in larger conducting airways rather than bronchioles, where epithelium transitions towards ciliated simple cuboidal epithelium with fewer secretory cells. The C-shaped cartilage rings are exclusive to the trachea and main bronchi and are not found in bronchioles. Submucosal tubuloalveolar glands are associated with larger bronchi and not with bronchioles, as these glands decrease in number and eventually disappear in the smaller airway passages.