A codon in m-RNA has :-

Options

A. 3-bases
B. 2-bases
C. 1-base
D. Number of bases vary

Answer

**Step-by-Step Solution:**

1. **Understanding Codons**: A codon is a sequence of three nucleotides in mRNA that corresponds to a specific amino acid or a stop signal during protein synthesis.

2. **Composition of Codons**: Each codon consists of three nucleotide bases. These bases can be any combination of the four nucleotides found in RNA: adenine (A), uracil (U), cytosine (C), and guanine (G).

3. **Function of Codons**: Codons are essential for translating the genetic information carried by mRNA into proteins. Each codon specifies a particular amino acid that will be added to the growing polypeptide chain during translation.

4. **Examples of Codons**:
- The start codon, which signals the beginning of protein synthesis, is AUG (adenine, uracil, guanine) and codes for the amino acid methionine.
- Stop codons, which signal the termination of protein synthesis, include UAA, UGA, and UAG. These do not code for any amino acid.

5. **Conclusion**: Therefore, a codon in mRNA has three bases.

**Final Answer**: A codon in mRNA has three bases.

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