Explain why the stomach is highly acidic and how the duodenum neutralizes acid entering from the stomach.

Explain why the stomach is highly acidic and how the duodenum neutralizes acid entering from the stomach.

• A. The stomach acid activates pepsin and kills pathogens; the duodenum neutralizes acid via bicarbonate from the pancreas and bile, aided by bicarbonate-rich mucus.
• B. The stomach acid neutralizes pathogens; the duodenum adds acid to digest proteins.
• C. The stomach is neutral; the duodenum uses acid to activate enzymes.
• D. The stomach uses bicarbonate; the duodenum uses water to neutralize.

Answer: (A)