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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
The pressure between the layers of the pleura is negative due to the following reasons:
assistant
The correct answer is  The tendency of the lungs and thoracic wall to recoil in the opposite direction expands the intrapleural space and creates negative pressure i.e. below the atmospheric pressure in between the two layers of pleura. Ref: Fundamentals of Respiratory Physiology By A. S. Chakrabay, Chakrabay, 2007, Page 33