Question

Degeneracy of the genetic code denotes the existence of
A. Multiple codons for a single amino acid
B. Wobble hypothesis
C. Base triplets that do not code for amino acids
D. All of the above

Answer 1

Hint: The genetic code refers to the three base-paired sequence framework on the DNA strand. These three-base sequences are called codons. There are a total of 64 codons. The codons are universal. One codon is for one amino acid production. But this code sometimes gets corrupted.

Complete step by step answer: Degeneracy of the genetic code means that there is some corruption in the coding of amino acids. The genetic code is referred to as universal. This means that if the codon codes for methionine amino acid in E.coli then the same codon will code for methionine in the human cell.
-It is known by extensive research that there are a total of 64 codons present for 20 amino acids. It was observed that some amino acids have more than one origin codon. Scientists deduced that some codons exhibit redundancy and thus are not ambiguous. This is called codon degeneracy.
So, let us see which option suits best for codon degeneracy.
Option A states that degeneracy of genetic codon denotes the existence of multiple codons for a single amino acid. It is true for codon degeneracy as the codons show the multiplicity of codon combinations that specify an amino acid.
Option B Wobble hypothesis states that the third base of anticodon on tRNA is flexible to base-pairing with more than one base on the codon bearing mRNA sequence. Thus, it results in the matching of more than one codon with the same tRNA producing the same amino acid as in the case of glycine. Thus, this helps in conducting codon degeneracy but not a part of it. It is a separate mechanism.
Option C states that codon degeneracy denotes the existence of base triplets that do not code for amino acids. In the 64 codons for amino acids, 61 are sense codons means that code for amino acids. The three codons that are UAA, UAG, UGA are stop codons or nonsense codons. They have no role in amino acid production but they terminate it.
Therefore, option A is correct.

Note: There are two methods by which the same amino acid can be specified by two or more codons. One of the methods is that the tRNA accepting the same amino acids are different for different similar codons. The other one is that one tRNA pairs with two or more similar codons.