question_answer 31)

  A fluid filled double membranous layer surrounds the lungs. Name it and mention its important function.

Answer:

                  A fluid filled double membranous layer that surrounds the lungs is called pleura, and fluid is pleural fluid in between them. The outer pleural membrane is in close contact with the thoracic lining whereas, the inner pleural membrane is in contact with the lung surface. These collectively reduce friction on lung's surface.