Question

Is the common bile duct the same as the bile duct?

Answer 1

The common bile duct is abbreviated as CBD. It is a duct in the gastrointestinal tract of organisms, having a gallbladder. It is formed by the confluence of the cystic duct and common hepatic duct and terminates by joining with the pancreatic duct, forming the ampulla of Vater. It is a part of the biliary duct system. The main function of CBD is the conduction of bile into the duodenum when the sphincter of Oddi is open

Complete answer:

                                               Fig: Parts of a Biliary Tree  

There are many types of bile ducts present in the biliary tree. The common bile duct is emptied by bile from all the bile ducts.
The biliary tree is divided into intrahepatic and extrahepatic bile ducts (EHBD).
Intrahepatic ducts are bile ducts from bile canaliculi up to the right and left hepatic ducts. Extrahepatic bile duct is inclusive of common hepatic ducts and hepatic ducts. EHBD links to a cystic duct, forming a common bile duct.
The pathway is as follows:
Bile canaliculi $\to$Canals of Herring $\to$interlobular bile ducts $\to$ right and left hepatic (lobar) ducts merging $\to$ common hepatic duct exiting liver and joins $\to$ cystic duct (from the gallbladder) forming $\to$ common bile duct $\to$joins with pancreatic duct $\to$ forms ampulla of Vater $\to$enters second part of the duodenum
The common bile duct is the largest of bile ducts in the biliary tree and is mostly the site for pathologies and blockage, the term bile duct is generally used as a synonym for common bile duct.

Note:
The functions of the biliary system are draining the waste products from the liver into the duodenum. In addition, the biliary system aids in the digestion of food products with the controlled and sustained release of bile. Bile is a greenish-yellow liquid, which is secreted by the liver cells. It carries away the waste and breaks the fats during the digestion process. Bile is excreted from the body, providing color to the feces.