The digestion of food is completed in the

Options

A. ileum
B. duodenum
C. stomach
D. large intestine

Answer

**Step-by-Step Solution:**

1. **Understanding the Digestive System:** The digestion of food occurs in the digestive system, specifically in the elementary canal, which is a long tube that processes food from ingestion to excretion.

2. **Starting Point - Buccal Cavity:** The process of digestion begins in the buccal cavity (mouth), where enzymes like amylase start breaking down starch. However, this is only the initial stage of digestion.

3. **Esophagus:** After the buccal cavity, food travels down the esophagus. It is important to note that no digestion occurs in the esophagus; it merely serves as a passageway to the stomach.

4. **Digestion in the Stomach:** The stomach is responsible for further digestion. It secretes gastric juice, which contains enzymes that primarily digest proteins. However, digestion is not complete in the stomach, as some peptides remain.

5. **Small Intestine - Major Site of Digestion:** The small intestine is where the majority of digestion occurs. It receives enzymes from both the pancreas and the small intestine itself. Here, carbohydrates, proteins, fats, and nucleic acids are completely digested.

6. **Parts of the Small Intestine:** The small intestine consists of three parts: the duodenum, jejunum, and ileum. The duodenum is connected to the stomach, and the ileum is the final part where complete digestion occurs.

7. **Large Intestine:** The large intestine primarily absorbs water and does not play a significant role in digestion. Therefore, it is not the site where digestion is completed.

8. **Conclusion:** Based on the information, the digestion of food is completed in the small intestine, specifically in the ileum.

**Final Answer:** The digestion of food is completed in the small intestine.

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