In inspiration the intrapleural pressure become: (PGI Dec 2006)
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 -Ganong22nd/651Fig (Ganong 23rd/592): Pressure in alveoli & the pleural space relative to atmospheric pressure during inspiration & expiration
More -ve
More + ve
Same as expiratory level
Initially positive then negative
Mechanics of Respiration