Final answer:
The duct that carries bile and combines with the pancreatic duct to enter the small intestine is known as the common bile duct. It joins the main pancreatic duct at the hepatopancreatic ampulla (ampulla of Vater) before releasing their contents into the duodenum, overseen by the hepatopancreatic sphincter.
Step-by-step explanation:
The duct that transports bile and merges with the pancreatic duct to enter the small intestine is called the common bile duct. This duct is formed by the union of the right and left hepatic ducts exiting the liver and the cystic duct from the gallbladder. It then joins with the main pancreatic duct near the duodenum. The point where these two ducts meet is called the hepatopancreatic ampulla (ampulla of Vater), which opens into the duodenum at the major duodenal papilla. The flow of bile and pancreatic juice into the duodenum is regulated by the hepatopancreatic sphincter (sphincter of Oddi).
Aside from its primary role, the common bile duct also works with the pancreatic duct to facilitate digestion. Pancreatic enzymes and bicarbonate, secreted by the exocrine part of the pancreas, travel through the main pancreatic duct, which further merges with the common bile duct. Through these ducts, digestive juices that aid in breaking down fats, carbohydrates, and proteins are delivered into the first section of the small intestine, the duodenum.