which one is the most abundent protein in the animal world ?

Options

A. Collagen
B. insulin
C. Trypsin
D. Haemoglobin

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the most abundant protein in the animal world.

2. **Recall Knowledge**: From biological studies, we know that proteins play various roles in the body, including structural, enzymatic, and regulatory functions.

3. **Consider Common Proteins**: Some well-known proteins include hemoglobin, myoglobin, and enzymes like Rubisco. However, these may not be the most abundant in animals.

4. **Focus on Collagen**: Collagen is a fibrous protein that is widely distributed in the animal kingdom, particularly in connective tissues such as skin, tendons, and bones.

5. **Confirm Abundance**: It is noted that collagen constitutes about 30% of the total protein content in the body of many animals, making it the most abundant protein in the animal world.

6. **Differentiate from Other Proteins**: While Rubisco is the most abundant protein overall in the biological world (including plants), collagen is specifically the most abundant in animals.

7. **Conclude the Answer**: Therefore, the answer to the question is that collagen is the most abundant protein in the animal world.

**Final Answer**: Collagen is the most abundant protein in the animal world.

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