Blood carrying digested food from the small intestine flows into the liver via the

Analyze the question: The question asks which vessel carries blood containing digested food from the small intestine into the liver.

Concept: After digestion, nutrients such as glucose and amino acids are absorbed into the blood capillaries of the villi in the small intestine. This blood does not go straight back to the heart. It first goes to the liver, which regulates nutrient levels, stores glycogen, and detoxifies harmful substances. The vessel that does this job is a portal vein. A portal vein connects two capillary networks: here, the intestinal capillaries and the liver sinusoids.

Step-by-step solution:

1. Digested food is absorbed into the capillaries of the villi in the small intestine.
2. The capillaries join to form the mesenteric veins, which join the hepatic portal vein.
3. The hepatic portal vein carries this nutrient-rich blood to the liver.
4. After processing, blood leaves the liver through the hepatic vein and goes to the vena cava.

Checking the options:

• A. Hepatic portal vein: correct. It carries blood from the intestine to the liver.
• B. Hepatic vein: carries blood away from the liver.
• C. Hepatic artery: brings oxygenated blood from the aorta to the liver. It does not carry digested food.
• D. Mesenteric artery: carries blood to the intestine from the aorta.
• E. Renal vein: carries blood away from the kidney.

Answer: A. Hepatic portal vein

Exam tip: Remember that the word "portal" means a gateway between two capillary beds. Also remember the order: Intestine → Hepatic portal vein → Liver → Hepatic vein → Vena cava → Heart. "Hepatic vein" leaves the liver, and "portal vein" enters it.