Question

Name the factors that affect therate of diffusion of gases in the lungs?

Answer 1

Factors affecting diffusion of gases are-

• Solubility of gases
• Thickness of membranes involved

• Partial pressure − Pressure contributed by an individual gas in a mixture of gases
• The pO₂ in oxygenated blood is 95 mm Hg while it is 40 mm Hg in tissues. Similar pressure gradient occurs for CO₂ in opposite direction i.e., 40 mm Hg in oxygenated blood and 45 mm Hg in tissues.
• Solubility of CO₂ is 20 - 25 times higher than that of oxygen. Therefore, CO₂ can diffuse at comparatively lesser concentration gradient also.

• These factors are favourable for diffusion of O₂ from alveoli to tissue and CO₂ from tissue to alveoli.