Surfactant production in lungs stas at:
**Core Concept**
Surfactant production in lungs is a crucial process that reduces surface tension in alveoli, facilitating easier lung expansion and preventing alveolar collapse during exhalation. This process is essential for maintaining normal respiratory function. Surfactant production involves the coordinated effort of various cell types, including type II pneumocytes and Clara cells.
**Why the Correct Answer is Right**
Surfactant production begins early in fetal development and continues after birth. Type II pneumocytes, the primary surfactant-producing cells, start producing surfactant as early as 24 weeks of gestation. The surfactant is secreted into the alveolar space, where it reduces surface tension and promotes lung expansion. This process is critical for lung maturation and the ability of the newborn to breathe at birth.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because surfactant production does not start immediately after birth. While surfactant is essential for newborn respiration, its production begins earlier in fetal development.
**Option B:** This option is incorrect because Clara cells, while involved in surfactant production, are not the primary surfactant-producing cells in the lungs.
**Option C:** This option is incorrect because the exact timing of surfactant production is not specified. While surfactant production does occur in the fetal lung, the precise timing is not accurately represented by this option.
**Clinical Pearl / High-Yield Fact**
The absence or deficiency of surfactant, often referred to as respiratory distress syndrome (RDS), is a leading cause of morbidity and mortality in preterm infants. Administering surfactant to preterm infants has been shown to significantly improve respiratory outcomes and reduce mortality rates.
**Correct Answer:** C.