In which part of the alimentary canal food is finally digested?

Options

A. Stomach
B. Mouth cavity
C. Large intestine
D. Small intestine

Explanation

**Step-by-Step Solution:**

1. **Understanding the Alimentary Canal**: The alimentary canal is the pathway through which food passes, including the mouth, esophagus, stomach, small intestine, and large intestine.

2. **Digestion Process Overview**: Digestion begins in the mouth, where food is mechanically broken down by teeth and chemically broken down by enzymes in saliva.

3. **Mouth**: In the mouth, the enzyme salivary amylase starts breaking down starch into simple sugars. This is both a physical and chemical process.

4. **Stomach**: After the mouth, food moves to the esophagus and then to the stomach. In the stomach, gastric juices containing pepsin begin the digestion of proteins into amino acids. However, this is only partial digestion.

5. **Small Intestine**: The food then moves into the small intestine, where the complete digestion of food occurs. The walls of the small intestine secrete intestinal juice, which contains enzymes that break down carbohydrates, fats, and proteins completely.

6. **Role of Pancreas and Liver**: The small intestine also receives pancreatic juice from the pancreas and bile from the liver, which aid in the digestion of food.

7. **Conclusion**: The final and complete digestion of food occurs in the small intestine.

**Final Answer**: The food is finally digested in the **small intestine**.

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