Glutathione is

Options

A. Protein
B. Tripeptide
C. Polysaccharide
D. Trisaccharide.

Answer

**Step-by-Step Solution:**

1. **Understanding Glutathione**: Glutathione is a molecule that plays a crucial role in various biological processes. It is important to identify its composition to determine its classification.

2. **Composition of Glutathione**: Glutathione is composed of three specific amino acids: glutamate, cysteine, and glycine. This composition is key to understanding its classification.

3. **Definition of Tripeptide**: A tripeptide is defined as a peptide that consists of three amino acids linked together by peptide bonds. Since glutathione is made up of three amino acids, it fits this definition.

4. **Eliminating Other Options**:
- **Protein**: Proteins are larger molecules made up of one or more polypeptides, typically consisting of many amino acids. Since glutathione only contains three amino acids, it cannot be classified as a protein.
- **Polysaccharide**: Polysaccharides are carbohydrates made up of long chains of monosaccharides. Glutathione does not fit this definition as it is composed of amino acids, not sugars.
- **Trisaccharide**: A trisaccharide is a carbohydrate made up of three monosaccharides. Again, glutathione does not fit this definition as it is not a carbohydrate.

5. **Conclusion**: Based on the composition and definitions, the correct classification of glutathione is that it is a tripeptide.

**Final Answer**: Glutathione is a tripeptide.

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