Surfactant plays a crucial role in respiratory health by preventing the alveoli from collapsing. It does this by interfering with the cohesiveness of water molecules, which significantly reduces the surface tension of the fluid lining the alveoli.
When the surface tension is high, the alveoli—tiny air sacs in the lungs—tend to collapse, especially during exhalation. Surfactant, which is composed of lipids and proteins, acts like a detergent, breaking the strong cohesive bonds between water molecules. This reduction in surface tension allows the alveoli to remain open, making it easier for gas exchange (like oxygen and carbon dioxide) to occur efficiently.
In summary, while surfactant does not specifically warm the air or provide a protective barrier for the alveolar surface,its primary function is to lower surface tension, thus preventing alveolar collapse and promoting effective breathing.