Which one of the following statements is true for protein synthesis `(` translation `)` ?

Options

A. Amino acids are directly recognized by m-RNA
B. The third base of the codon is less specific
C. Only one codon codes for an amino acid
D. Every t-RNA molecule has more than one amino acid attachment site

Answer

To determine which statement is true for protein synthesis (translation), let's analyze each option step by step.

### Step-by-Step Solution:

1. **Option A: Amino acids are directly recognized by the mRNA.**
- This statement is **incorrect**. Amino acids are not recognized directly by mRNA. Instead, tRNA molecules recognize the codons on the mRNA through their anticodons, and then they carry the corresponding amino acids to the ribosome for protein synthesis.

2. **Option B: The third base of the codon is less specific.**
- This statement is **correct**. According to the wobble hypothesis, the third base of a codon can vary without affecting the amino acid that is specified. This means that the third base is less specific compared to the first two bases, allowing for some flexibility in codon-anticodon pairing.

3. **Option C: Only one codon codes for an amino acid.**
- This statement is **incorrect**. The genetic code is degenerate, meaning that multiple codons can code for the same amino acid. For example, there are several codons that specify the amino acid leucine.

4. **Option D: Every tRNA molecule has more than one amino acid attachment site.**
- This statement is **incorrect**. Each tRNA molecule has only one specific attachment site for a particular amino acid. This specificity is crucial for accurate translation.

### Conclusion:
The only true statement regarding protein synthesis (translation) is **Option B: The third base of the codon is less specific.**

---