Our lungs work hard. Even when we’re resting, they diligently carry oxygen through the bloodstream and remove carbon dioxide from the blood. They are part of a complex system, managed by a complicated structure of organs and tissues: our respiratory system.
When we inhale, through the nose or mouth, air moves from the throat up the windpipe to divide into two main bronchial tubes that carry air to each lung (and there are cells never seen before). These pipes then yes branch into smaller passages called bronchioleswhich carry air to small air sacs called alveoli.
This is where oxygen from the air can be absorbed into hemoglobin and carbon dioxide can be vented into the atmosphere.
Since the gaseous exchanges between the inside and the outside of the pulmonary alveolus, i.e. between the inside of the organism and the atmospheric gases, are phenomena that take place at the contact surface, in order to be efficient they need a huge surface development. It is for this reason that they are truly enormous.
The total contact area of both lungs is approx equivalent to the surface area of a tennis court and the total length of the airways that cross them is more than 2414 kilometers: double the distance from Catania to Milan. By the way, did you know that doctors once found a plant inside the lungs?