Where is protein digestion accomplished

Options

A. Stomach
B. Ilium
C. Rectum
D. Duodenum

Explanation

**Step-by-Step Solution:**

1. **Understanding Protein Digestion**: Protein digestion begins in the stomach and continues in the small intestine. The primary enzymes involved in protein digestion are called proteases.

2. **Identifying the Key Locations**: The main locations for protein digestion are:
- **Stomach**: Here, proteins are denatured by stomach acid and partially digested by the enzyme pepsin.
- **Duodenum**: This is the first part of the small intestine where additional enzymes from the pancreas (like trypsin and chymotrypsin) are released to further digest proteins.
- **Ileum**: This is the final part of the small intestine, where the absorption of nutrients occurs, including the end products of protein digestion (amino acids).

3. **Analyzing the Options**:
- **A. Stomach**: Protein digestion starts here, but it is not where it is completed.
- **B. Ileum**: This is primarily for absorption rather than digestion.
- **C. Rectum**: This is part of the digestive tract but not involved in protein digestion.
- **D. Duodenum**: This is where significant protein digestion occurs due to the action of pancreatic enzymes.

4. **Conclusion**: While the ileum is important for absorption, the majority of protein digestion is accomplished in the duodenum. Therefore, the correct answer is **D. Duodenum**.