Final answer:
The pulmonary circuit carries deoxygenated blood from the right side of the heart to the lungs for oxygenation and brings back oxygenated blood to the left side of the heart.
Step-by-step explanation:
The circuit that carries deoxygenated blood from the right side of the heart and brings oxygenated blood back to the left side of the heart is known as the pulmonary circuit. Deoxygenated blood flows into the right atrium from the body through the superior and inferior vena cava, then to the right ventricle, which pumps it through the pulmonary arteries to the lungs for oxygenation. After receiving oxygen in the lungs, the oxygenated blood is carried back to the left atrium via the pulmonary veins, completing the pulmonary circuit. The left side of the heart then sends this oxygenated blood throughout the body via the systemic circuit, which ultimately brings blood back to the right side of the heart to repeat the cycle.