Final answer:
The efficiency of alveolar gas exchange is affected by the size of the airway, lung compliance, surface tension in the alveoli, and the balance between ventilation and perfusion (V/Q match).
Step-by-step explanation:
The efficiency of alveolar gas exchange is influenced by four main factors:
- Size of the airway: Narrow airways increase resistance and limit gas flow.
- Lung compliance: The ease with which the lungs can stretch affects their ability to take in air.
- Surface tension in alveoli: This can inhibit expansion, but is reduced by the presence of pulmonary surfactant.
- Ventilation-perfusion (V/Q) match: Efficient gas exchange requires a balance between the air reaching the alveoli (ventilation) and the blood reaching the alveoli (perfusion).
Resistance is created by the diameter of the airways and inelastic surfaces, while lung compliance affects the potential volume of the lungs. Pulmonary surfactant decreases the surface tension to prevent alveolar collapse.
The balance between ventilation and perfusion (V/Q match) is critical for effective gas exchange; any imbalance, due to factors like disease or gravity effects on blood, can impede this process. The interplay between these factors determines the movement of oxygen and carbon dioxide according to their partial pressure gradients.