What vein collects pure blood from the posterior parts of the body to the heart?

The vein that collects deoxygenated blood from the posterior parts of the body and returns it to the heart is the inferior vena cava. It gathers blood from the lower regions, including the legs, abdomen, and pelvis, and transports it to the right atrium of the heart. The superior vena cava serves a similar function for the upper parts of the body. Together, they ensure that blood circulates back to the heart for reoxygenation.