Vitamins often act as

Options

A. Holoenzymes
B. Co-enzymes
C. Apoenzymes
D. Cofactors

Answer

**Step-by-Step Solution:**

1. **Understanding Enzymes**: Enzymes are biological catalysts that speed up chemical reactions in the body. They can be composed of proteins alone or proteins combined with non-protein components.

2. **Defining Cofactors**: Cofactors are non-protein molecules that assist enzymes in their function. They can be either organic or inorganic.

3. **Types of Cofactors**: Cofactors are categorized into two main types:
- **Coenzymes**: These are organic molecules, often derived from vitamins, that assist enzymes in catalyzing reactions.
- **Prosthetic Groups**: These are inorganic molecules (such as metal ions like iron, cobalt, or nickel) that are tightly or permanently bound to enzymes.

4. **Role of Vitamins**: Vitamins are organic compounds that are essential for various metabolic processes in the body. They often serve as coenzymes, meaning they help enzymes function effectively.

5. **Conclusion**: Based on the definitions and roles discussed, vitamins often act as coenzymes in enzymatic reactions.

**Final Answer**: Vitamins often act as coenzymes.

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