Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of these

Options

A. are exclusively synthesized in the body of a living organism as at present
B. help in regulating metabolism
C. enhance oxidative metabolism
D. are conjugated proteins

Answer

To solve the question regarding the classification of enzymes, vitamins, and hormones as biological chemicals, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Components**:
- Identify what enzymes, vitamins, and hormones are.
- **Enzymes**: Biological catalysts that speed up chemical reactions in the body.
- **Vitamins**: Organic compounds that are essential for normal growth and nutrition, typically obtained from the diet.
- **Hormones**: Chemical messengers that regulate various physiological processes in the body.

2. **Analyzing the Options**:
- The question provides four options to classify these biomolecules. We will evaluate each option to find the correct one.

3. **Evaluating Option 1**:
- "They are exclusively synthesized in the body of a living organism."
- This is incorrect because not all vitamins are synthesized in the body; many must be obtained from the diet.

4. **Evaluating Option 2**:
- "They help in regulating the metabolism."
- This is correct. Enzymes facilitate metabolic reactions, vitamins often act as cofactors in these reactions, and hormones play a crucial role in regulating metabolic processes.

5. **Evaluating Option 3**:
- "They enhance oxidative metabolism."
- This statement is misleading as it applies primarily to enzymes. Vitamins and hormones do not universally enhance oxidative metabolism, making this option incorrect.

6. **Evaluating Option 4**:
- "They are all conjugated proteins."
- This is incorrect because while some enzymes are proteins, hormones can be proteins, steroids, or other types of molecules, and not all of them are conjugated proteins.

7. **Conclusion**:
- After evaluating all the options, the correct classification of enzymes, vitamins, and hormones as biological chemicals is that they help in regulating metabolism (Option 2).

### Final Answer:
The correct classification is that enzymes, vitamins, and hormones help in regulating the metabolism.

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