Bronchioles

Bronchioles are the small air passageways in the lungs that branch off from the bronchi. They are part of the respiratory system and play a crucial role in delivering air to the alveoli, where gas exchange occurs.

Structure of Bronchioles

Bronchioles are small, thin-walled tubes that lack cartilage and are surrounded by smooth muscle. They further divide into smaller passages known as terminal bronchioles, which eventually lead to the alveolar ducts and alveolar sacs.

Function of Bronchioles

The main function of bronchioles is to regulate airflow and distribute air to the alveoli. They achieve this through the contraction and relaxation of the smooth muscle surrounding their walls, which controls the diameter of the airways. This process, known as bronchoconstriction and bronchodilation, respectively, helps in regulating the flow of air into the lungs based on the body's oxygen needs.

Study Guide

1. Structure: Describe the structure of bronchioles and how they differ from the bronchi.
2. Function: Explain the primary function of bronchioles in the respiratory system and their role in gas exchange.
3. Regulation: Discuss how the smooth muscle in bronchioles helps regulate airflow and the concept of bronchoconstriction and bronchodilation.
4. Relation to Alveoli: Describe how bronchioles are connected to the alveolar ducts and sacs, and their role in delivering air to these structures.

[Bronchioles] Related Worksheets and Study Guides:

• Organ systemsScience • Fourth Grade