Bronchial artery supplies up to (AIPG -2008)
1. Bronchial arteries are the branches from the descending thoracic aorta and supplies till the level of respiratory bronchiole (B).
2. They perfuse the proximal air conducting pathways including tertiary (A) and terminal (D) bronchioles and reach till the beginning of respiratory unit.
3. Pulmonary arteries alone have to vascularize the further distal pathways, including alveolar ducts (C) and the alveoli.
4. There are pre-capillary anastomoses between bronchial & pulmonary arteries, at the level of respiratory bronchioles, thus strengthening the dual vasculature of lungs.