A : In bacterial translation mechanism, either of the two tRNA are required by methionine.
R: AUG codes for methionine and it shows non ambiguity also.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark 1
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion , then mark
C. If Assertion is true statement but Reason is false, then mark 3
D. If both Assertion and Reason are false statements, then mark 4.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**: The assertion states that in the bacterial translation mechanism, either of the two tRNAs are required by methionine. This means that during protein synthesis in bacteria, methionine can be brought to the ribosome by two different tRNA molecules.

2. **Identifying the tRNAs**: In bacterial translation, the two tRNAs that can carry methionine are:
- The initiator tRNA (which recognizes the start codon AUG).
- The tRNA that can recognize the codon GUG (which can also code for methionine).

3. **Understanding the Reason (R)**: The reason states that AUG codes for methionine and shows non-ambiguity. This means that the codon AUG specifically codes for the amino acid methionine and does not code for any other amino acid.

4. **Explaining Non-Ambiguity**: Non-ambiguity in the genetic code indicates that each codon corresponds to only one specific amino acid. For example, AUG will always code for methionine, ensuring that there is no confusion in the translation process.

5. **Evaluating the Truth of A and R**: Both the assertion and the reason are true statements:
- The assertion is true because methionine can indeed be brought by either of the two tRNAs (AUG or GUG).
- The reason is also true because AUG does code for methionine and is non-ambiguous.

6. **Determining the Relationship**: However, the reason provided does not directly explain the assertion. Although both statements are true, the reason does not clarify why either of the two tRNAs is required for methionine.

7. **Conclusion**: Therefore, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

**Final Answer**: Both A and R are true, but R is not the correct explanation for A.

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