Bird, lung (LM, Low)

Structure List Parabronchi Atria Hexagonal septum Vessels Muscular pillars Higher Magnification View

This field shows a cross section of a parabronchus and its associated gas exchange area. Note the muscles in the walls of the parabronchus. These muscular pillars separate atria from each other. From the atria, the air capillaries project into the surrounding vascular bed. The parabronchus is surrounded by a connective tissue septum which delineates a hexagonal cross section. There are pulmonary arteries and veins located at the corners of this hexagon. Identify them.