What is the primary function of the hepatic vein?

The primary function of the hepatic vein is to carry blood away from the liver. After the liver processes the blood, which has flowed into it from the portal vein and hepatic artery, the hepatic veins collect this deoxygenated blood and transport it back to the heart. This is crucial because the liver plays an essential role in metabolism, detoxification, and storage of nutrients. Once the liver has filtered and modified the blood, it must return this cleansed blood to the systemic circulation to maintain proper physiological balance.

The other options, while related to the functions of the liver and its blood supply, do not accurately describe the role of the hepatic vein. The hepatic artery is responsible for supplying oxygenated blood to the liver, while filtering toxins is a key function of the liver itself, and the portal system is related to the blood supply to the liver but involves the portal vein carrying blood to the liver rather than the hepatic vein carrying it away.