A premature infant born at 30 weeks gestation develops respiratory distress shortly after birth. Which of the following best explains the developmental basis for this condition?
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AIncomplete formation of the tracheal cartilaginous rings
BDelayed closure of the ductus arteriosus
CUnderdeveloped intercostal muscles
DInsufficient surfactant production by type II pneumocytes
✓ Correct answer: D. Insufficient surfactant production by type II pneumocytesSurfactant production by type II pneumocytes typically begins around weeks 22-24 but doesn't reach adequate levels until approximately 34-36 weeks gestation. Premature infants born before sufficient surfactant production are at high risk for respiratory distress syndrome due to poor alveolar stability, increased surface tension, and alveolar collapse, leading to impaired gas exchange.
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Theory