The right pulmonary artery is a major blood vessel that carries deoxygenated blood from the heart's right ventricle to the right lung. It is part of the pulmonary circulation system, which is responsible for transporting blood to the lungs for oxygenation. Once in the right lung, the blood passes through smaller branches of the right pulmonary artery, allowing for gas exchange in the alveoli. This process is essential for replenishing oxygen in the blood and removing carbon dioxide, supporting overall respiratory function and health.