Answer :
Final answer:
Muscular waves in the stomach mix the meal with gastric juices for digestion. Sodium bicarbonate in pancreatic juices then neutralizes the acidic chyme in the small intestine. The Correct Answer is Option.B.
Explanation:
Muscular waves in the stomach, known as mixing waves, actively combine and churn the contents of a meal with gastric juices. These mixing waves facilitate mechanical digestion, a process where food is broken down into a semi-liquid form called chyme, which is then mixed with various digestive enzymes.
When chyme enters the small intestine, it is mixed with pancreatic juices, an alkaline solution rich in sodium bicarbonate. The role of the sodium bicarbonate is to buffer and neutralize the acidic nature of the chyme, providing an optimal pH environment for digestive enzymes to function.