Related Experiment Video
Updated: Aug 18, 2026

A Microfluidic Model of Biomimetically Breathing Pulmonary Acinar Airways
Published on: May 9, 2016
Beyond the principle of similitude: renormalization in the bronchial tree
Abstract:
The average dimensions (diameter, length, and volume) of the airways in the mammalian bronchial tree, long thought to be exponential functions of the generation number, are shown to be power laws in generation number modulated by a harmonic variation. These data are satisfactorily described by means of a functional scaling relation--renormalization group property--between successive generations for the average variable of interest. This type of scaling may provide a mechanism for the morphogenesis of complex but highly stable structures.
Related Concept Videos
The Respiratory System
The Bronchial Tree
The trachea, commonly known as the windpipe, is a tube that connects the larynx (voice box) to the bronchi. At a point called the carina, it bifurcates into two primary bronchi. The right primary bronchus is wider, shorter, and more vertical than the left primary...
Gross Anatomy of the Lungs
External and Internal Respiration
Anatomy of Respiratory System II: Lower Respiratory Tract
The Larynx
It is located between the pharynx and the trachea, acts as a passageway for air, and hosts several critical structures, such as the epiglottis, vocal cords, and glottis. The epiglottis acts as a gateway, guiding food to the...
Chronic Obstructive Pulmonary Disease III: Chronic Bronchitis Features

