David Barlow's video: Bronchii in the Lung

An endoscopic journey down successively dividing airways (Bronchii) in a pig's lung. Many pig organs are almost indistinguishable from human ones and so make good models to study. The airflow is being marked by a fine mist of water particles to simulate the inhalation of particulate substances such as smoke or allergens like dust or pollen. The allergens can penetrate a long way into the lung and cause adverse effects. After several more divisions, you eventually reach the Alveoli where Oxygen is actually absorbed from the air into the blood and excess Carbon Dioxide removed. The distance of travel is limited by the diameter of the endoscope (4mm in this case). So that is the diameter of the airways at the end of the travel. The largest airway, the Trachea is about one inch in diameter and is slightly oval in shape. This clip can be found in the film archive at: http://www.davidbarlowarchive.com/record/4679 More similar shots can be found at: http://www.davidbarlowarchive.com/categories/physiology/airways/