Instead of 3, if it was 2 bases code for an amino acid, the degeneracy of codons coding for the same amino acid would have
Instead of 3, if it was 2 bases code for an amino acid, the degeneracy of codons coding for the same amino acid would have
The correct option is B Decreased
In genetic code table, each box is specified by the first and second positions (for example the AAX box, in which X is any of the four bases) therefore eight of the sixteen boxes contain just one amino acid per box. This means codon need only be read in the first two positions for these eight amino acids because the same amino acid will be represented regardless of the third base of the codon. That’s why multiple codons specify single amino acid and make the genetic code degenerate. According to the question, an amino acid that was encoded by three codons is now encoded by two codons. This means that degeneracy for that codon has been decreased. If the degeneracy was increased, a number of codons specifying the amino acid would have increased which makes option A wrong. If the degeneracy was same, the number of codons for the amino acid would remain same; this makes option C wrong. The correct answer is B.
In genetic code table, each box is specified by the first and second positions (for example the AAX box, in which X is any of the four bases) therefore eight of the sixteen boxes contain just one amino acid per box. This means codon need only be read in the first two positions for these eight amino acids because the same amino acid will be represented regardless of the third base of the codon. That’s why multiple codons specify single amino acid and make the genetic code degenerate. According to the question, an amino acid that was encoded by three codons is now encoded by two codons. This means that degeneracy for that codon has been decreased. If the degeneracy was increased, a number of codons specifying the amino acid would have increased which makes option A wrong. If the degeneracy was same, the number of codons for the amino acid would remain same; this makes option C wrong. The correct answer is B.
