State true or false:
Attachment of smaller unit of ribosome on mRNA bring the initiation codon at A site.

Answer

To determine whether the statement "Attachment of smaller unit of ribosome on mRNA brings the initiation codon at A site" is true or false, let's analyze the process of translation step by step.

### Step-by-Step Solution:

1. **Understanding Ribosome Structure**:
- Ribosomes are composed of two subunits: a smaller subunit and a larger subunit. In eukaryotes, these are referred to as 40S (small) and 60S (large), while in prokaryotes, they are 30S (small) and 50S (large).

**Hint**: Remember the ribosomal subunit sizes and their composition in different organisms.

2. **Role of mRNA in Translation**:
- mRNA (messenger RNA) carries the genetic information from DNA and serves as a template for protein synthesis during translation.

**Hint**: Consider how mRNA functions as a template in the translation process.

3. **Initiation of Translation**:
- The process of translation begins with the binding of the smaller ribosomal subunit to the mRNA. This binding occurs at the 5' end of the mRNA and scans for the start codon (AUG).

**Hint**: Focus on the importance of the start codon in the initiation phase of translation.

4. **Positioning of the Initiation Codon**:
- When the smaller ribosomal subunit binds to the mRNA, it positions the start codon (AUG) at the P site of the ribosome, not the A site. The A site is where the next aminoacyl-tRNA will bind.

**Hint**: Recall the specific roles of the A site and P site in the ribosome during translation.

5. **Conclusion**:
- Since the statement claims that the attachment of the smaller unit of the ribosome brings the initiation codon to the A site, and we have established that the initiation codon is actually positioned at the P site, the statement is **False**.

### Final Answer:
**False**