Question

Which blood vessel carries blood from the kidneys back to the heart?

Answer 1

Hint: Blood vessels are the arteries or conduits that carry blood to and from body tissues. The vessels are two closed networks of tubes that start and end at the heart. The pulmonary vessels are one system that carries blood from the right ventricle to the lungs and back to the left atrium.

Complete answer:
The kidneys play an important role in the body's urine output. They also play a part in the regulation of vital blood components.
The kidneys are also in charge of red blood cell formation. When the kidneys do not receive enough oxygen, they send out a distress signal in the form of erythropoietin development. Erythropoietin is a hormone that causes the bone marrow to produce more oxygen-carrying red blood cells.
The right and left renal arteries branching off the abdominal aorta provide oxygenated blood to the kidneys. Deoxygenated blood is expelled from the kidneys through the right and left renal veins, which connect to the inferior vena cava.
The renal vein exits the kidneys and returns blood to the heart. Since the kidneys remove nitrogenous metabolic wastes, the renal vein will have the least amount of nitrogenous metabolic wastes. The hepatic artery and vein transport blood into and out of the liver.

Note:
After kidneys have completed their filtering function, the filtered, deoxygenated blood exits the kidneys via the renal vein, ascends the inferior vena cava, and returns to the heart via the vena cava.