True about pulmonary surfactant is
Pulmonary surfactant is a mixture of lipids and proteins which is secreted into the alveolar space by epithelial type II cells. The main function of surfactant is to lower the surface tension at the air/liquid interface within the alveoli of the lung Ref: guyton and hall textbook of medical physiology 12 edition page number: 318,319,320
Secreted by type I pneumocytes
Maintain alveolar integrity
Cytokeratin
Mucin
Respiratory system