Which one is the most abundant protein in the animal world

Options

A. collagen
B. insulin
C. trypsin
D. haemoglobin

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the most abundant protein in the animal world among the given options: collagen, insulin, trypsin, and hemoglobin.

2. **Analyzing Each Option**:
- **Option A: Collagen**: Collagen is a structural protein found in the extracellular matrix and is crucial for the integrity of connective tissues. It forms a triple helix structure which contributes to its strength and stability. Collagen is widely distributed in various tissues, including skin, bones, tendons, and ligaments.

- **Option B: Insulin**: Insulin is a hormone produced by the pancreas that regulates glucose levels in the blood. While it is an important protein, it is not present in large quantities compared to structural proteins.

- **Option C: Trypsin**: Trypsin is a digestive enzyme also produced by the pancreas, responsible for breaking down proteins in the digestive system. It plays a vital role in digestion but is not as abundant as collagen.

- **Option D: Hemoglobin**: Hemoglobin is the protein in red blood cells that carries oxygen. While it is essential for oxygen transport, it is not as abundant as collagen in the overall animal body.

3. **Conclusion**: After analyzing all the options, it is clear that collagen is the most abundant protein in the animal world due to its widespread presence in connective tissues and the extracellular matrix.

4. **Final Answer**: The most abundant protein in the animal world is **collagen** (Option A).

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