**Question: How many different single-nucleotide substitutions* (changing one nucleotide to another) in the DNA sequence shown below can result in non-sense mutations (a stop codon replaces an amino acid codon) in the second generation in a bacterial strain that is defective in DNA repair?****Amino Acids**: Gln, Trp, Thr, Arg**Coding strand**: 5’-CAA TGG ACT CGA-3‘**For your information, Stop codons**: TAA, TAG, TGA**Note**: *Ignore Insertions, and Deletions for this question**Answer choices**:- None of these options- 16- 4- 1- 2### Explanation:This problem is related to mutations in a DNA sequence that cause the termination of protein synthesis at the substitution point, resulting in a non-sense mutation. It provides the current DNA sequence, the amino acids it codes for, and the possible stop codons that could be introduced due to nucleotide substitutions.### Detailed Explanation of Choices:The coding strand provided is 5’-CAA TGG ACT CGA-3‘. By changing one nucleotide at a time (single-nucleotide substitutions), we need to determine how many such changes can produce a stop codon (TAA, TAG, TGA).### Step-by-Step Analysis:1. **CAA** - Change C to T: TAA (Stop codon) - Change A to T: CTA (Not a stop codon) - Change A to G: CAG (Not a stop codon)2. **TGG** - Change T to A: AGG (Not a stop codon) - Change T to C: CGG (Not a stop codon) - Change G to A: TAG (Stop codon)3. **ACT** - Change A to T: TCT (Not a stop codon) - Change A to G: GCT (Not a stop codon) - Change T to A: ACA (Not a stop codon)4. **CGA** - Change C to T: TGA (Stop codon) - Change G to A: CAA (Not a stop codon) - Change A to G: CGG (Not a stop codon)From the above changes, we see the following possible single

Name: **Question: How many different single-nucleotide substitutions* (chan
Uploaded: 2024-03-20T06:42:41.000Z
Channel: Bartleby
Description: **Question: How many different single-nucleotide substitutions* (changing one nucleotide to another) in the DNA sequence shown below can result in non-sense mutations (a stop codon replaces an amino acid codon) in the second generation in a bacteria