Answer:
The replacement of a base at a codon, as occurs when the GGA codon is changed to CGA, causes a change in the amino acid glycine to arginine.
Explanation:
Nitrogen base changes in a codon usually result from base changes in the DNA before transcription into messenger RNA, called point gene mutations.
<em>In the case presented, the </em><em><u>substitution of the guanine base by cytosine in the GGA codon —resulting in a CGA codon— generates a change in the coding amino acid, resulting in arginine instead of glycine</u></em><em>.</em>
The change of an amino acid in a peptide or protein can mean an alteration in the structure or function of these molecules.
Because an amino acid can be encoded by several codons, changes of a nitrogen base at a codon sometimes do not involve changes in the amino acid sequence of a protein.