Final answer:
The function of lung surfactant is to reduce the surface tension within the alveoli, which prevents their collapse, facilitates inflation, and promotes more efficient gas exchange. Surfactants also help maintain lung compliance and equalize air distribution in the lungs.
Step-by-step explanation:
The role of lung surfactant is crucial for the functioning of our respiratory system. A surfactant is a complex mixture of phospholipids and lipoproteins, and its primary function is to reduce the surface tension in the alveoli. By doing so, surfactant prevents the collapse of alveoli during exhalation and facilitates their inflation during inhalation, much like applying a detergent to the inside of a balloon makes it easier to blow up. This is particularly important in maintaining lung stability, as it counteracts the natural tendency of the liquid present in the alveoli to create a high surface tension, which would otherwise cause alveoli to collapse and make breathing much more effortful.
This process also helps to maintain lung compliance, which is the ability of the lungs to stretch. An increased lung compliance leads to greater lung volume and lowered air pressure within the lungs during inhalation, thereby promoting more efficient gas exchange. It's noteworthy, too, that the presence of surfactant helps with the uniform distribution of air in the lungs, preventing smaller alveoli from collapsing and larger ones from overinflating.