Question

Pressure within the lungs is called

• A. Inter-pulmonary pressure
• B. Intra-pulmonary pressure
• C. Interstitial pressure
• D. Alveolar pressure

Answer 1

Answer: (B)

Intra-pulmonary pressure

In physiology, intrapleural pressure (also called intrathoracic pressure) refers to the pressure within the pleural cavity. Normally, the pressure within the pleural cavity is slightly less than the atmospheric pressure, in what is known as negative pressure.

When the pleural cavity is damaged/ruptured and the intrapleural pressure becomes equal to or exceeds the atmospheric pressure, pneumothorax may ensue. Intrapleural pressure depends on the ventilation phase, atmospheric pressure, and the volume of the intrapleural cavity. The logic in intrapulmonary pressure and the intrapleural pressure is that the pressure becomes more negative during inspiration and allows air to get sucked in (Boyle 's law.) P vs V relationship.....and during expiration the pressure becomes less negative and ( greater than atmospheric pressure, Note :[ the partial pressure of Carbon dioxide.] ) and the air is given out... The only difference in the pressures are intra-pleural pressure is more negative than intra-pulmonary pressure.

So, the correct answer is B.