Hepatic portal vein delivers blood to the liver for detoxification

Steps:

• Identify the path: Hepatic portal vein carries blood from small intestine directly to liver.
• Confirm destination: Liver receives this blood for initial processing before systemic circulation.
• Evaluate functions: Liver metabolizes toxins like alcohol from absorbed nutrients.
• Rule out alternatives: No direct path to kidneys; bile secretion occurs separately.

Why B is correct:

• Hepatic portal vein transports blood to liver, where alcohol dehydrogenase enzymes break down alcohol into acetaldehyde and further metabolites.

Why the others are wrong:

• A: Portal blood goes to liver, not kidneys; glucose delivery occurs systemically via arterial blood.
• C: Urea forms in liver from ammonia, then enters general circulation for kidney filtration, not direct from portal vein.
• D: Liver produces bile for secretion into small intestine via ducts, not addition to blood.

Final answer: B