Final answer:
Pancreatic juice drains into the duodenum, the initial part of the small intestine immediately after the stomach, where it mixes with bile to aid digestion.
Step-by-step explanation:
The pancreatic juice drains into the duodenum, which is the first segment of the small intestine, immediately following the stomach. The duodenum is described as a "C-shaped" segment that starts at the pyloric sphincter and wraps around the head of the pancreas. Pancreatic juices, which are rich in bicarbonate and contain various digestive enzymes, enter the duodenum to mix with the acidic chyme from the stomach and help in the digestion of starches, proteins, and fats. Moreover, bile that is produced in the liver and concentrated in the gallbladder also enters the duodenum where it emulsifies lipids. This critical process of mixing chyme with pancreatic juices and bile takes place in the duodenum, allowing for the breakdown and subsequent absorption of nutrients.