A.Intrapulmonary pressure is always negative
B.Thoracic cage and lungs are elastic
C.Transpulmonary pressure determines the negativity
D.Surfactant prevents the lungs to collapse
The correct answer is : B.Thoracic cage and lungs are elastic
NOTE:
B.Thoracic cage and lungs are elastic
C.Transpulmonary pressure determines the negativity
D.Surfactant prevents the lungs to collapse
The correct answer is : B.Thoracic cage and lungs are elastic
NOTE:
- Both the thoracic cage and lungs are elastic structures.
- Being elastic structure they both tend to recoil but in opposite direction
- The thoracic cage has inherent tendency to expand,while trying to expand,it draws the parietal pleura with it.
- The lungs have an inherent tendency to collapse because of their elasticity and surface tension of thin layer of fluid lining the alveoli.
- As the visceral pleura is strongly attached with the lungs,the pull in opposite directions of the visceral and parietal pleura,creates a negative intra-pleural pressure.
Negative Intrapleural pressure |