The pulmonary circulation carries deoxygenated blood from the heart to the lungs, and oxygenated blood from the lungs to the left ventricle.
Physiologically, is a high-flow, low-pressure system that accepts 100% of the cardiac output in adults.
Histologically, the vessels are thin-walled, with decreased musculature compared to the systemic circulation.
Tracing the path of a blood cell, it travels from the right ventricle, through the pulmonary trunk, pulmonary arteries (elastic, muscular, non-muscular), to the pulmonary capillaries, where it recevives some blessed oxygen. Then to the pulmonary vein, the right atrium, LV, and aorta.
The bronchial circulation arises from the left and right bronchial arteries (from aorta), which supply the bronchi. 2/3 of the bronchial veins then drain into the pulmonary veins, forming a shunt.