Into which part of the gastrointestinal tract does acid chyme move after leaving the stomach?

• A. Mouth
• B. Esophagus
• C. Duodenum
• D. Large intestine

Answer: (C)

After leaving the stomach, acid chyme enters the duodenum, which is the first part of the small intestine. The pyloric sphincter regulates gastric emptying and releases chyme into this section. In the duodenum, chyme mixes with bicarbonate from the pancreas and bile, neutralizing acid and providing enzymes for digestion. This makes the duodenum the primary site where the stomach’s contents begin to be chemically digested in earnest and prepared for absorption downstream. The mouth and esophagus are earlier in the route, and the large intestine handles mainly water absorption and waste processing, not the initial digestion of chyme.