What are the small branches off the bronchi called?

The branches off the bronchi are called bronchioles. These are smaller tubes that extend from the main bronchi into the lungs and lead to the alveoli, which are the tiny air sacs where gas exchange occurs. Bronchioles play a crucial role in the respiratory system by regulating airflow and distributing air to the alveoli. Their structure differs from the bronchi, as they are smaller, do not have cartilage in their walls, and are lined with smooth muscle and epithelial cells. This allows for the adjustment of airflow resistance and the distribution of air throughout the lung tissue effectively.

Alveoli refer to the air sacs at the end of the bronchioles where oxygen and carbon dioxide exchange takes place. Pleura are the membranes surrounding the lungs, providing lubrication and facilitating movement during respiration. Lobes are larger sections of the lungs, each subdivided into smaller segments. Understanding these distinctions clarifies the function and organization of the respiratory system.