Final answer:
Breathing properly requires surfactant, a substance that reduces surface tension in the alveoli and prevents them from collapsing, ensuring efficient gas exchange in the lungs.
Step-by-step explanation:
Breathing properly requires the presence of a compound that affects the surface tension of alveoli in the lungs. This compound is known as surfactant, which is a complex mixture of phospholipids and lipoproteins that reduces the surface tension between the alveoli tissue and the air in the alveoli. By lowering the surface tension of the alveolar fluid, surfactant prevents the alveoli from collapsing during exhalation and ensures proper lung function.
Conditions like hyaline membrane disease in premature infants or respiratory distress in drowning victims can occur due to the lack of adequate surfactant, underscoring its critical role in respiratory health. Treatment often involves administering surfactant to aid in lung inflation and prevent alveolar collapse. Surfactant also differs from detergents as it changes wall tension, thereby stabilizing both small and large alveoli during respiratory cycles.