tRNA attached to mRNA by its

Options

A. I loop
B. II loop
C. III loop
D. IV loop

Answer

To answer the question "tRNA attached to mRNA by its...", we need to understand the structure of tRNA and how it interacts with mRNA during protein synthesis.

### Step-by-Step Solution:

1. **Understanding tRNA Structure**:
- tRNA (transfer RNA) is a small RNA molecule that plays a crucial role in translating the genetic code from mRNA into proteins. It has a cloverleaf structure with several loops.

2. **Identifying the Loops**:
- tRNA consists of four main loops:
- **Acceptor Arm**: This is where the amino acid attaches.
- **TΨC Loop**: This loop helps in the recognition of the ribosome.
- **Variable Loop**: This region varies among different tRNAs and does not have a specific function related to mRNA binding.
- **Anticodon Loop**: This loop contains the anticodon, which is a sequence of three nucleotides that is complementary to the codon on the mRNA.

3. **Role of the Anticodon Loop**:
- The anticodon loop is crucial for the attachment of tRNA to mRNA. The anticodon pairs with the corresponding codon on the mRNA strand during translation.

4. **Conclusion**:
- Therefore, the tRNA attaches to mRNA specifically through its **anticodon loop**.

### Final Answer:
The tRNA is attached to mRNA by its **anticodon loop**.

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