What do type 2 pneumocytes produce that is essential for reducing surface tension in the alveoli?

Type 2 pneumocytes, also known as type II alveolar cells, are specialized cells found in the alveoli of the lungs. One of their primary functions is to produce pulmonary surfactant, a substance that plays a crucial role in maintaining proper respiratory function. Surfactant is composed largely of phospholipids and proteins and is essential for reducing surface tension at the air-liquid interface within the alveoli.

Reducing surface tension is vital because it prevents the collapse of alveoli during exhalation, thereby enhancing lung compliance and facilitating gas exchange. Without sufficient surfactant, alveoli can become unstable, leading to conditions such as atelectasis, where parts of the lung collapse, significantly impairing breathing and oxygenation. Hence, the production of surfactant by type 2 pneumocytes is critical for effective pulmonary function and overall respiratory health.