Final answer:
Surfactant is vital for lung function, reducing surface tension in the alveoli to prevent collapse and promote efficient gas exchange. It is particularly important in preventing respiratory distress in premature infants who may not produce enough surfactant.
Step-by-step explanation:
The substance known as surfactant plays a critical role in lung function by reducing surface tension within the alveoli, which are the tiny air sacs in the lungs where gas exchange occurs. Surfactant is composed mainly of phospholipids and lipoproteins, and their primary function is to lower the surface tension between the tissue of the alveoli and the air inside them. This action mitigates the tendency of the alveoli to collapse, especially during exhalation when the lung volume decreases and pressure within the alveoli could potentially cause them to deflate.
By decreasing the surface tension, surfactant ensures that small alveoli don't collapse and helps to prevent larger alveoli from overinflating, thus maintaining stability within the lung's structure and function. When the alveoli remain properly inflated, it promotes efficient gas exchange by allowing for consistent intake of oxygen and release of carbon dioxide. Inadequate surfactant levels can lead to respiratory distress, as seen in premature infants who may suffer from respiratory distress syndrome due to insufficient surfactant production.