What type of blood circulation supplies the alveoli for gas exchange?

• A. Pulmonary circulation
• B. Bronchial circulation
• C. Systemic circulation
• D. Coronary circulation

Answer: (A)

The correct response highlights the role of pulmonary circulation in supplying blood to the alveoli for gas exchange. Pulmonary circulation is specifically designed to transport deoxygenated blood from the right ventricle of the heart to the lungs. In the lungs, the blood flows through the pulmonary arteries and enters the capillary networks surrounding the alveoli.

Within this region, gas exchange occurs as carbon dioxide is expelled from the blood, and oxygen is absorbed into the blood. The oxygenated blood then returns to the left atrium of the heart through the pulmonary veins, completing the cycle. This process is essential because it directly facilitates the exchange of gases, which is critical for maintaining proper oxygen levels in the body.

Other types of circulation, such as bronchial circulation, systemic circulation, and coronary circulation, have different functions. Bronchial circulation supplies oxygenated blood to the tissues of the lungs themselves, but is not primarily responsible for gas exchange. Systemic circulation is focused on delivering oxygenated blood to the rest of the body, and coronary circulation refers specifically to the supply of blood to the heart muscle itself. Thus, while all these circulatory pathways are important, pulmonary circulation is the only one that directly functions in the gas exchange process in the alveoli.