Which part of the cardiovascular system is responsible for returning blood back to the heart?

Veins are the part of the cardiovascular system responsible for returning blood back to the heart. After blood circulates through the body, delivering oxygen and nutrients to tissues via arteries and arterioles, it returns to the heart through veins. Veins have thinner walls compared to arteries and often have one-way valves to prevent backflow, facilitating the return of blood, especially from the lower parts of the body, against the force of gravity. This process is essential for maintaining proper circulation and ensuring that the heart can efficiently pump blood to the lungs for oxygenation and then back out to the rest of the body.