North American Registry of Midwives (NARM) Practice Exam

Which of the following is NOT required for surfactant production in fetal lungs?

1. Oxygen

2. Glucose

3. Lactic acid

4. Lung perfusion

The correct answer is: Lactic acid

Surfactant production in the fetal lungs is essential for proper lung function after birth. It primarily involves the activity of type II alveolar cells, which are responsible for synthesizing and secreting surfactant. Oxygen is critical for surfactant production because the alveolar cells need it for metabolic processes that lead to the synthesis of surfactant proteins and lipids. Likewise, glucose is necessary as it serves as a primary energy source for cellular metabolism, which is vital for the production of surfactant components. Lung perfusion involves blood flow to the lungs, which is important for nutrient uptake and maintaining the overall health of lung tissues during development. Lactic acid, on the other hand, is not a requirement for surfactant production in fetal lungs. While lactic acid may accumulate as a byproduct of anaerobic metabolism under certain conditions, it does not play a direct role in the synthesis or secretion of surfactant. Therefore, it is correct to identify lactic acid as not being required for surfactant production.