Chapter 20 - Section 20.6 - Study Guide - Assess Your Learning Outcomes - Page 799: 3

The pulmonary circuit and the bronchial arteries are two distinct systems that supply blood to the lungs, each serving different functions. 1. **Pulmonary Circuit:** The pulmonary circuit is responsible for oxygenating the blood and removing carbon dioxide. Deoxygenated blood from the body is pumped by the right side of the heart into the pulmonary arteries, which carry it to the lungs. In the lungs, the pulmonary arteries branch into smaller vessels, eventually leading to the pulmonary capillaries surrounding the alveoli. In these capillaries, oxygen diffuses from the alveoli into the blood, while carbon dioxide diffuses out of the blood into the alveoli. The oxygen-rich blood then returns to the heart through the pulmonary veins, which connect to the left side of the heart, allowing the oxygenated blood to be pumped to the rest of the body. 2. **Bronchial Arteries:** The bronchial arteries are a separate set of arteries that supply oxygenated blood to the lung tissue itself, not for the purpose of gas exchange. These arteries branch off from the aorta (the main artery that carries oxygenated blood from the heart to the body) and provide oxygen and nutrients to the bronchial tubes, supporting the lung tissue's metabolic needs. While the lungs primarily receive oxygen through the pulmonary circuit (exchange of gases between alveoli and blood), the bronchial arteries ensure that the lung tissue itself is adequately supplied with oxygen-rich blood. In summary, the key difference between the functions of the pulmonary circuit and the bronchial arteries lies in their purpose: the pulmonary circuit is focused on gas exchange between the alveoli and blood, facilitating oxygen uptake and carbon dioxide removal, while the bronchial arteries provide oxygenated blood to support the metabolic needs of the lung tissue itself.

The pulmonary circuit and the bronchial arteries are two distinct systems that supply blood to the lungs, each serving different functions. 1. **Pulmonary Circuit:** The pulmonary circuit is responsible for oxygenating the blood and removing carbon dioxide. Deoxygenated blood from the body is pumped by the right side of the heart into the pulmonary arteries, which carry it to the lungs. In the lungs, the pulmonary arteries branch into smaller vessels, eventually leading to the pulmonary capillaries surrounding the alveoli. In these capillaries, oxygen diffuses from the alveoli into the blood, while carbon dioxide diffuses out of the blood into the alveoli. The oxygen-rich blood then returns to the heart through the pulmonary veins, which connect to the left side of the heart, allowing the oxygenated blood to be pumped to the rest of the body. 2. **Bronchial Arteries:** The bronchial arteries are a separate set of arteries that supply oxygenated blood to the lung tissue itself, not for the purpose of gas exchange. These arteries branch off from the aorta (the main artery that carries oxygenated blood from the heart to the body) and provide oxygen and nutrients to the bronchial tubes, supporting the lung tissue's metabolic needs. While the lungs primarily receive oxygen through the pulmonary circuit (exchange of gases between alveoli and blood), the bronchial arteries ensure that the lung tissue itself is adequately supplied with oxygen-rich blood. In summary, the key difference between the functions of the pulmonary circuit and the bronchial arteries lies in their purpose: the pulmonary circuit is focused on gas exchange between the alveoli and blood, facilitating oxygen uptake and carbon dioxide removal, while the bronchial arteries provide oxygenated blood to support the metabolic needs of the lung tissue itself.