During the translation process , the ATP molecule is required for

Options

A. Association of 50S subunit of the ribosome with the initiation complex .
B. Binding of 305 subunit of the ribosome with Mrna
C. Association of 30S - mRNA with formyl - met - tRNA .
D. Charging of tRNA

Answer

**Step-by-Step Solution:**

1. **Understanding Translation**: Translation is the process by which proteins are synthesized from messenger RNA (mRNA). This involves ribosomes, transfer RNA (tRNA), and various factors that facilitate the process.

2. **Role of ATP in Translation**: ATP (adenosine triphosphate) is a crucial energy molecule in cellular processes, including translation. It provides the energy required for various steps in this complex process.

3. **Identifying the Options**:
- **A. Association of 50S subunit of ribosome with initiation complex**: This step primarily involves GTP (guanosine triphosphate) rather than ATP.
- **B. Binding of 30S subunit of ribosome with mRNA**: This also does not require ATP; it is facilitated by other factors.
- **C. Association of 30S mRNA with formyl-Met-tRNA**: This step is crucial for initiation but does not directly require ATP.
- **D. Charging of tRNA**: This is the process where amino acids are attached to their corresponding tRNA molecules, and it requires ATP. This process is also known as aminoacylation.

4. **Conclusion**: The correct answer is **D. Charging of tRNA**, as ATP is specifically required for this step in the translation process.

**Final Answer**: D. Charging of tRNA

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