Reasoning Questions in Respiratory System

1. Why do premature newborns develop respiratory distress syndrome?

• Type II pneumocytes are immature because of which there is inadequate surfactant causing increase in surface tension leading to alveolar collapse (atelectasis). Type II pneumocytes mature at 24 to 28 weeks of gestation.

2. Why can a person voluntarily hold their breath only for a limited time?

• Rising CO₂ and falling O₂ stimulate chemoreceptors which override cortical control and automatic breathing resumes.