Describe the systemic circuit. (Module 19.1B) Describe the systemic circuit. (Module 19.1B) The systemic circuit transports blood from the right ventricle through the pulmonary arteries, capillaries in the lungs, and pulmonary veins and returns it to the left atrium. The systemic circuit transports blood through the arteries, capillaries, and veins of the body from the left ventricle to the right atrium. The systemic circuit consists of the vasculature in the heart. The systemic circuit transports blood from the left ventricle through the pulmonary arteries, capillaries in the lungs, and pulmonary veins and returns it to the right atrium. The systemic circuit transports blood from the left ventricle through the pulmonary veins, capillaries in the lungs, and pulmonary arteries and returns it to the right atrium.