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Which of the following accurately describes silent mutations? a. A silent mutation does not alter the DNA sequence of a gene, and does not change the mRNA and polypeptide sequences generated by expression of the gene. b. A silent mutation changes the DNA sequence of a gene, but does not alter the mRNA or polypeptide sequences generated by expression of the gene. c. A silent mutation changes the DNA sequence of a gene and the mRNA sequence produced by transcription of the gene, but does not alter the polypeptide sequence generated by translation. d. A silent mutation changes the DNA sequence of a gene, and changes both the mRNA and polypeptide sequences produced by expression of a gene.

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User NoriSte
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Final answer:

A silent mutation is a type of point mutation where a change in the DNA sequence does not alter the final protein sequence. This occurs due to the redundancy of the genetic code, where multiple codons can code for the same amino acid.

Step-by-step explanation:

The accurate description of silent mutations among the provided options is: c. A silent mutation changes the DNA sequence of a gene and the mRNA sequence produced by transcription of the gene, but does not alter the polypeptide sequence generated by translation. Silent mutations are a type of point mutation in which a change in the DNA sequence does not result in a change to the protein structure. This happens because multiple combinations of the three-letter codons can code for the same amino acid due to the redundancy of the genetic code, hence, a change in a DNA sequence can still code for the same amino acid. In other words, despite the change, the altered codon still results in the same amino acid during protein synthesis.

For instance, the codons AGA, AGG, CGA, CGC, CGG, and CGU all code for the amino acid arginine. If a DNA mutation alters an AGA (arginine) codon to AGG, CGA, CGC, CGG, or CGU, it remains a codon for arginine - hence a silent mutation. These mutations demonstrate the degeneracy of the genetic code, where multiple codons can code for a single amino acid.

Learn more about Silent Mutations

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User Chuckg
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