Bilirubin
Bilirubin is a vital waste compound that is eliminated from the body with the help of bile. Hemoglobin, which is found in red blood cells, contains heme – a red pigment. As the body breaks down red blood cells, it separates heme molecules from hemoglobin. These heme molecules are then converted into biliverdin through a series of processes. Eventually, biliverdin is further broken down into bilirubin, which gives bruises and jaundice their characteristic yellow color.
Biliary Tract
The biliary tract refers to the pathway through which bile travels from the liver to the small intestine. It all starts with the secretion of bile by hepatocytes into small ducts called bile canaliculi. These tiny ducts merge together to form bile ductules, which eventually join to form the common hepatic duct. From the liver, the common hepatic duct connects to the cystic duct of the gallbladder. The cystic duct and the common hepatic duct combine to form the common bile duct. As the journey continues, the common bile duct joins the pancreatic duct. Together, these ducts pass through the ampulla of Vater and enter the duodenum of the small intestine.