Bronchi

Definition

The bronchi are major air passages that branch off from the trachea into the lungs. They play a crucial role in conducting air to and from the respiratory zones of the lungs.

5 Must Know Facts For Your Next Test

1. The bronchi are divided into primary, secondary, and tertiary bronchi based on their order of branching.
2. Primary bronchi enter each lung and then further divide into secondary bronchi for each lobe of the lung.
3. The walls of the bronchi contain cartilage and smooth muscle, which help keep them open and allow for regulation of airflow.
4. Normal microbiota present in the bronchi include various bacteria such as Streptococcus and Neisseria species.
5. Bronchitis is an inflammation of the bronchi often caused by infections or irritants.

Review Questions

• What structural features distinguish primary, secondary, and tertiary bronchi?
• How do the normal microbiota in the bronchi contribute to respiratory health?
• What role does smooth muscle play in the function of the bronchi?

Related terms

Trachea:

A tube that connects the larynx to the bronchi, allowing air passage to and from the lungs.

Alveoli:

Tiny air sacs within the lungs where gas exchange occurs between air and blood.

Bronchitis: Inflammation of the bronchial tubes usually caused by infection or other factors like smoking.