TABLE 134 Some Important Facts About Pulmonary surfactant 1. Pulmonary surfactant is a mixture of phospholipids and protein 2. It is secreted by type II alveolar cells 3. It lowers the surface tension of the water layer at the alveolar surface, which increases lung compliance (i.e, makes the lungs easier to expand) 4. Its surface tension is lower in smaller alveoli thus stabilizing alveoli cells). Its concentration decreases when breaths are small( 5. a deep breath increases its secretion(by stretching the type 6. Production in the fetal lung occurs in late gestation