Bronchial Tree
The mammalian respiratory system mirrors vascular branching: the trachea bifurcates into two bronchi, which subdivide into bronchioles, which terminate in alveoli.
The mammalian respiratory system mirrors vascular branching: the trachea bifurcates into two bronchi, which subdivide into bronchioles, which terminate in alveoli. Humans have ~23 generations of airway branching, culminating in ~300-500 million alveoli with total surface area ~70 m² - packed into lungs occupying ~6 liters.
This fractal architecture solves the surface-area problem. The bronchial tree's fractal dimension is ~2.9, nearly filling three-dimensional space, enabling surface area to scale almost linearly with volume rather than volume^(2/3) as the square-cube law would predict.
Notable Traits of Bronchial Tree
- 23 generations of airway branching
- 300-500 million alveoli
- 70 m² surface area in 6 liters
- Fractal dimension ~2.9