Which of the following elements helps in maintaining the structure of ribosomes?

Options

A. Magnesium
B. Zinc
C. Copper
D. Molybdenum

Answer

To solve the question regarding which element helps in maintaining the structure of ribosomes, we can follow these steps:

### Step-by-step Solution:

1. **Understanding Ribosomes**: Ribosomes are cellular structures responsible for protein synthesis. They come in two types: 70S and 80S. Each type consists of two subunits.

2. **Identifying Ribosome Composition**:
- **70S Ribosome**: Composed of a larger subunit (50S) and a smaller subunit (30S).
- **80S Ribosome**: Composed of a larger subunit (60S) and a smaller subunit (40S).

3. **Role of Elements in Ribosome Structure**: The two subunits of ribosomes need to be properly assembled to form functional ribosomes.

4. **Element Required for Assembly**: The assembly of the ribosomal subunits requires a specific element. In this case, magnesium ions (Mg²⁺) are crucial for maintaining the structure of ribosomes.

5. **Concentration of Magnesium**: The effective concentration of magnesium required for the proper assembly of ribosomal subunits is approximately 0.001 molar.

6. **Conclusion**: Therefore, the element that helps in maintaining the structure of ribosomes is magnesium.

### Final Answer:
The element that helps in maintaining the structure of ribosomes is **magnesium (Mg²⁺)**.

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