Multiple choice Which of the following contains highest concentration of urea? Renal artery Hepatic vein Hepatic artery Renal Vein Reveal answer Fill a bubble to check yourself B Correct answer Explanation A hepatic vein carries oxygen depleted blood out of the liver, with highest concentration of urea, into the inferior vena cava. The term vein refers to a blood vessel, that transports blood back to the heart. The term hepatic, relates to the liver.