The reasoning: a detergent recycled through the ileum
Liver receives ~25% of cardiac output (portal vein ~75%, hepatic artery ~25% — the "hepatic arterial buffer response" raises arterial flow when portal flow falls). Functions: glucose homeostasis (glycogen, gluconeogenesis), lipid and lipoprotein metabolism, urea cycle, plasma protein synthesis (albumin, clotting factors, binding proteins), biotransformation (phase I CYP450, phase II conjugation), hormone inactivation, storage (glycogen, vitamins A, D, B12, iron, copper), immune filtering (Kupffer cells), bile formation.