🫁 Gas Exchange in Lungs
Interactive Illustration of Oxygen and Carbon Dioxide Diffusion
Alveolus (Air Sac) Blood Capillary Respiratory Membrane O₂ CO₂ Concentration Levels: O₂: High in alveolus O₂: Low in blood CO₂: High in blood CO₂: Low in alveolus Diffusion Process: 1. Oxygen Movement: • High O₂ in alveolus • Low O₂ in blood • O₂ diffuses into bloodstream 2. Carbon Dioxide Movement: • High CO₂ in blood • Low CO₂ in alveolus • CO₂ diffuses into alveolus for exhaling
🔵 Oxygen Diffusion
Direction: Alveolus → Blood
Reason: Higher O₂ concentration in inhaled air
Result: Oxygen enters bloodstream for transport to body cells
🔴 Carbon Dioxide Diffusion
Direction: Blood → Alveolus
Reason: Higher CO₂ concentration in blood from cellular respiration
Result: CO₂ removed from body through exhaling
🎯 Key Learning Points
Diffusion in Action: Gas exchange in the lungs demonstrates how diffusion works based on concentration gradients. Oxygen moves from high concentration (alveolus) to low concentration (blood), while carbon dioxide moves in the opposite direction. This passive process requires no energy and is essential for cellular respiration and waste removal.
💡 This illustration shows simplified molecular movement. In reality, millions of gas molecules are exchanged simultaneously across the respiratory membrane.
Last modified: Thursday, 31 July 2025, 3:11 PM