Which vessel carries nutrient-rich blood from the gut to the liver?

• A. Aorta
• B. Renal vein
• C. Hepatic artery
• D. Hepatic portal vein

Answer: (D)

The key idea is how nutrient-filled blood from the digestive tract reaches the liver through a special circulation. After nutrients are absorbed in the gut, the blood travels through the hepatic portal system and is carried to the liver by the hepatic portal vein. This vessel brings nutrient-rich (and relatively low in oxygen) blood from the digestive organs to the liver, where nutrients can be processed, stored, or detoxified before the blood joins the general circulation. The hepatic artery, by contrast, supplies oxygen-rich blood directly to the liver but does not transport gut nutrients. The aorta carries systemic blood away from the heart, and the renal vein drains the kidney. So the hepatic portal vein is the route that delivers gut-derived nutrients to the liver.