Which one is the major constituent of proteins, nucleic acids, vitamins and hormones?

Options

A. (a) P
B. (b) N
C. (c) K
D. (d) S

Explanation

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the major constituent of proteins, nucleic acids, vitamins, and hormones.

2. **List the Options**: The options provided are:
- A) Phosphorus
- B) Nitrogen
- C) Potassium
- D) Sulphur

3. **Understand the Biomolecules**: Recognize that proteins, nucleic acids, vitamins, and hormones are all types of biomolecules. Each of these biomolecules has specific elements that are crucial for their structure and function.

4. **Analyze Each Option**:
- **Phosphorus**: Primarily found in nucleic acids (as part of the backbone) and some phospholipids, but not a major constituent in proteins and hormones.
- **Nitrogen**: A key component of amino acids (which make up proteins), nitrogenous bases (in nucleic acids), and is also present in some vitamins and hormones.
- **Potassium**: An essential mineral for various cellular functions but not a major component of proteins, nucleic acids, vitamins, or hormones.
- **Sulphur**: Present in some amino acids (like cysteine and methionine) and certain vitamins, but not as widespread as nitrogen.

5. **Determine the Major Constituent**: Among the options, nitrogen is the most significant element that is a major component of proteins (through amino groups), nucleic acids (in nitrogen bases), vitamins, and hormones.

6. **Conclude the Answer**: Therefore, the correct answer is **Option B: Nitrogen**.

### Final Statement:
Hence, Nitrogen is the major constituent of proteins, nucleic acids, vitamins, and hormones.

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