Which Is TRUE About the Pleural Sac

question 31

Multiple Choice

Which is TRUE about the pleural sac?

• A)It is continuous with the atmosphere and protects the lungs from infection.
• B)It is a closed sac surrounding each lung that contains only a tiny volume of lubricating fluid.
• C)It is a closed sac surrounding each lung and contains a large volume of surfactant.
• D)It is a closed,air-filled space surrounding both lungs that has a negative pressure compared to atmospheric pressure.
• E)It is bounded by pleural membranes that are very thin,which allows for abundant gas exchange.

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Definitions:

Dielectric Oil

A type of insulating oil often used to cool transformers.

Insulator

A material or device that resists the flow of electric current, used to prevent undesired current flow.

Cooling

The process of removing heat from an object or space, often to maintain a desired temperature.

Phase Current

The electric current flowing through one phase of a multi-phase system, like in three-phase electrical systems.