Final answer:
The pancreatic duct and the common bile duct converge at the hepatopancreatic ampulla, which opens into the duodenum and regulates the flow of digestive juices through the sphincter of Oddi.
Step-by-step explanation:
The structures that unite at the hepatopancreatic ampulla, also known as the ampulla of Vater, are the pancreatic duct and the common bile duct. The pancreatic duct, or the duct of Wirsung, carries enzyme-rich pancreatic juice from the pancreas, whereas the common bile duct results from the union of the common hepatic duct and the cystic duct, carrying bile from the liver and gallbladder. These two ducts merge before entering the duodenum at the major duodenal papilla. The regulation of bile and pancreatic juice into the small intestine is controlled by the smooth muscle sphincter known as the hepatopancreatic sphincter (sphincter of Oddi).
The structures that unite at the hepatopancreatic ampulla, or ampulla of Vater, are the pancreatic duct and the common bile duct. Located in the duodenal wall, this ampulla marks the transition from the anterior portion of the alimentary canal to the mid-region. It is where the bile duct, through which bile passes from the liver, and the main pancreatic duct, through which pancreatic juice passes from the pancreas, join. The ampulla opens into the duodenum via a volcano-shaped structure called the major duodenal papilla, and the hepatopancreatic sphincter regulates the flow of both bile and pancreatic juice from the ampulla into the duodenum.