How does gas exchange occur between alveolar air and blood?
By diffusion across the alveolar and capillary walls.
AQA GCSE Combined Science: Trilogy (8464) — Biology — Foundation · 4.1.3.1
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How does gas exchange occur between alveolar air and blood?
By diffusion across the alveolar and capillary walls.
In which directions do oxygen and carbon dioxide diffuse during alveolar gas exchange?
Oxygen: alveolar air → blood. Carbon dioxide: blood → alveolar air.
How do numerous alveoli help gas exchange?
They provide a large surface area for diffusion.
How does the thin alveolar epithelium help gas exchange?
It gives a short diffusion distance between air and blood.
What role does the moist alveolar surface play in gas exchange?
It allows gases to dissolve before diffusing.
How does a rich capillary supply help alveolar gas exchange?
It helps maintain concentration gradients.
How does ventilation help maintain concentration gradients in the alveoli?
It replenishes alveolar air.