THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -It is established that pulmonary surfactant reduces surface tension at the air–water interface in the alveoli, thereby preventing collapse of these structures at end-expiration.

Detailed explanation-2: -Surfactant is a complex substance containing phospholipids and a number of apoproteins. This essential fluid is produced by the Type II alveolar cells, and lines the alveoli and smallest bronchioles. Surfactant reduces surface tension throughout the lung, thereby contributing to its general compliance.

Detailed explanation-3: -Alveolar type II cells secrete a lipoprotein material called surfactant, whose primary function is to reduce the surface tension in the alveoli. Surfactant is a lipoprotein that consists mainly of dipalmitoylphosphatidylcholine and some glycoprotein components.