<prompt> In inspiration the intrapleural pressure become: PGI Dec 2006More -veMore veSame as expiratory levelInitially positive then negative  <response>: Ans: A More negative The intrapleural pressure at the base of lungs, which is normally about -2.5 mm Hg relative to atmospheric at the start ofinspiration, decreases to about-6 mm of HgQ- Ganong 22nd 651Strong inspiratory efforts can reduce intrapleural pressure to values as low as -30 mm Hg -Ganong22nd651Fig Ganong 23rd592: Pressure in alveoli the pleural space relative to atmospheric pressure during inspiration expiration 