Respiratory System — Tech Evolutions

Entry	Year	Description	Impact
N/A (Scientific Advancement)	1950s-1960s	Discovery of Surfactant's Role: The understanding of pulmonary surfactant, a lipoprotein complex secreted by Type II pneumocytes, revolutionized the understanding of alveolar mechanics. Its role in reducing surface tension and preventing alveolar collapse, particularly in premature infants (Respiratory Distress Syndrome), was a major scientific breakthrough.	Led to the development of surfactant replacement therapy, significantly improving survival rates for premature babies. Enhanced understanding of lung mechanics and disease pathophysiology, influencing respiratory medicine and critical care.
N/A (Policy Shift)	2019 (Launch)	National Clean Air Programme (NCAP): While not a constitutional amendment, the launch of NCAP by the Ministry of Environment, Forest and Climate Change marked a significant policy shift towards a national framework for air quality management. It aims to reduce particulate matter concentration by 20-30% by 2024 (with 2017 as base year) in 131 non-attainment cities.	Represents a concerted governmental effort to address air pollution, a major contributor to respiratory diseases. Its implementation and effectiveness are crucial for improving public respiratory health and are highly relevant for UPSC governance and environment topics.