Which of the following essential element is used in the synthesis of proteins ?

Options

A. Carbon
B. Sulphur
C. Potassium
D. Nitrogen

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which essential element is used in the synthesis of proteins.

2. **Identifying the Components of Proteins**: Proteins are made up of smaller units called amino acids.

3. **Recognizing the Role of Amino Acids**: Amino acids contain specific functional groups, including an amino group (-NH2) and a carboxyl group (-COOH).

4. **Identifying the Key Element**: The amino group contains nitrogen, which is a crucial element in the structure of amino acids.

5. **Analyzing the Options**:
- Option 1: Carbon - While it is a part of the structure, it is not the key element for protein synthesis.
- Option 2: Sulfur - Present in some amino acids but not essential for all proteins.
- Option 3: Potassium - Not directly involved in protein synthesis.
- Option 4: Nitrogen - Essential for the formation of the amino group in amino acids.

6. **Conclusion**: The correct answer is nitrogen because it is essential for the synthesis of proteins through the formation of amino acids.

**Final Answer**: The essential element used in the synthesis of proteins is **Nitrogen** (Option 4).

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