What will help in protein digestion in stomach ?

Options

A. Pepsin
B. Trypsin
C. Ptyalin
D. Rennin.

Answer

To answer the question "What will help in protein digestion in the stomach?", we need to analyze the options provided and understand the role of each enzyme in the digestive process.

### Step-by-Step Solution:

1. **Identify the Enzymes**: The options given are pepsin, trypsin, tylene, and ranine. We will evaluate each enzyme to determine its role in protein digestion.

2. **Pepsin**:
- Pepsin is secreted by the chief cells of the stomach in an inactive form known as pepsinogen.
- Pepsinogen is activated to pepsin by hydrochloric acid (HCl) present in the stomach.
- Pepsin is specifically responsible for breaking down proteins into smaller peptides and peptones in the stomach.
- **Conclusion**: Pepsin is the primary enzyme that aids in protein digestion in the stomach.

3. **Trypsin**:
- Trypsin is another protein-digesting enzyme, but it is secreted by the pancreas in an inactive form called trypsinogen.
- Trypsinogen is activated in the small intestine, not the stomach.
- Therefore, trypsin functions in the small intestine, not in the stomach.
- **Conclusion**: Trypsin does not help in protein digestion in the stomach.

4. **Tylene**:
- Tylene is not a protein-digesting enzyme; it is a salivary amylase that aids in the digestion of starch.
- **Conclusion**: Tylene is incorrect as it does not assist in protein digestion.

5. **Ranine**:
- Ranine is a protein-digesting enzyme but is primarily found in ruminants (like cows and calves) and is involved in digesting milk proteins.
- It is not present in the human stomach.
- **Conclusion**: Ranine does not help in protein digestion in the human stomach.

### Final Answer:
The correct answer to the question is **Pepsin** (Option A), as it is the only enzyme that aids in protein digestion in the stomach.

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