If the Thoracic Wall Is Punctured,air Leaking in Will Cause

question 6

Multiple Choice

If the thoracic wall is punctured,air leaking in will cause the lung to collapse.Thus one can conclude that in the normal intact thoracic cavity,

• A) lung expansion is passive.
• B) air pressure is the same as it is on the outside.
• C) air pressure is lower than it is on the outside,which helps keep the lungs inflated.
• D) breathing movements keep the lungs inflated.
• E) Both a and b