Functional proteins is
(a) Enzyme
(b) Collagen
(c) ossein
(d) Vitamin

Options

A. Enzyme
B. Collagen
C. ossein
D. Vitamin.

Answer

To determine which of the given options is a functional protein, let's analyze each option step by step:

1. **Understanding Functional Proteins**:
- Functional proteins are proteins that perform specific biological functions. They are involved in various processes in the body, such as catalyzing biochemical reactions, transporting molecules, and providing structural support.

2. **Analyzing Option (a) Enzyme**:
- Enzymes are biological catalysts that speed up chemical reactions in the body. They are made up of proteins and have an active site where substrates bind. Enzymes lower the activation energy required for reactions, making them essential for metabolic processes. Therefore, enzymes are considered functional proteins.

3. **Analyzing Option (b) Collagen**:
- Collagen is a structural protein that provides support and strength to various tissues, such as skin, bones, and cartilage. While it is an important protein in the body, it does not have a catalytic function like enzymes do. Thus, collagen is not classified as a functional protein.

4. **Analyzing Option (c) Ossein**:
- Ossein is a type of collagen found in bones. Similar to collagen, it provides structural support but does not perform a functional role like catalyzing reactions. Therefore, ossein is not a functional protein.

5. **Analyzing Option (d) Vitamin**:
- Vitamins are organic compounds that are essential for normal growth and nutrition. They are not proteins and do not perform functions like enzymes do. Hence, vitamins are not classified as functional proteins.

6. **Conclusion**:
- Based on the analysis, the only option that qualifies as a functional protein is (a) Enzyme.

**Final Answer**: (a) Enzyme

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