The alveolar surface is lined by a coherent liquid-crystalline phase
The existence of a uniform phase at the alveolar surface is demonstrated by polarizing microscopy and cryogenic transmission electron microscopy (cryo-TEM). Rabbit lungs were opened and the alveolar surface film was directly deposited on optical microscope coverslips and on electron microscope grids. In the polarizing microscope, the alveolar surface material deposited exhibits a uniform birefring
