Why do lungs have branching tubes?
The short answer
Branching airways deliver air across many air sacs and create a large surface for gas exchange.
How it works
The windpipe divides into bronchi and then smaller bronchioles. Tiny air sacs at the ends exchange gases with nearby capillaries.
A familiar example
Thinking of a tree-like network helps show why air is distributed over a wide surface instead of through one tube.