Final answer:
The characteristic 'overlapping' is not a correct feature of the genetic code. The code is triplet, degenerate, commaless, and unambiguous, but codons are not read in an overlapping fashion. The correct answer is option 4.
Step-by-step explanation:
The genetic code is a set of rules that determines the correspondence between the sequence of nucleotides in mRNA and the sequence of amino acids in proteins. Let's review the given characteristics of the genetic code:
Degenerate: This is a correct characteristic of the genetic code. Degeneracy refers to the fact that multiple codons can code for the same amino acid. For example, the amino acid leucine has six different codons (e.g., UUA, UUG, CUU, CUC, CUA, CUG) that all specify leucine.
Commaless: This is also a correct characteristic. The genetic code lacks punctuation or "commas" between codons. It is a continuous, non-overlapping sequence of nucleotide triplets that is read during translation.
Unambiguous: This is correct. Each codon in the genetic code specifies a single amino acid. There is no ambiguity in the translation process, with each codon having a specific amino acid assignment.
Triplet code: This is correct. The genetic code operates on a triplet basis, where three nucleotides (a codon) correspond to a specific amino acid or a stop signal.
Overlapping: This is not a characteristic of the standard genetic code. Overlapping refers to a situation where a single nucleotide may be part of more than one codon, resulting in a reading frame that can encode multiple, overlapping amino acid sequences. However, in the standard genetic code, codons are non-overlapping, and each nucleotide is part of only one codon.
Therefore, the characteristic that is not accurate among the options provided for the genetic code is 4) Overlapping.