Here are parts of the DNA base sequences for 7 organisms:

Organism 1: GCCTAGGCATTACGCTACGTCGCATTATAC

Organism 2: GCTAAGGCACTACGCTACGTCGCTTAATAG

Organism 3:
GCTAAGCACTACGCTACGTCGCTTAATAGC

Organism 4:
GCTAAGGCACTACGCTACGTCGCATTATAC

Organism 5:
GCCAAGGCACTACGCTACGTCGCATTATAC

Organism 6:
GCTAAGGCACTACGCTACGTCGCTTTATAC

Organism 7:
GCTAAGAGACTACGGAACGCCGCTTAATAG

The question is: Which of the sequences is least likely to lead to a functional part of a protein, and why?

I researched stop codons in DNA and found them to be TAG, TAA and TGA - which doesn't help as pretty much all of the sequences feature one of these at least once.

Any help would be appreciated, thanks!

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To determine which sequence is least likely to lead to a functional part of a protein, we need to look for specific start and stop codons. Start codon is always AUG, and stop codons can be TAG, TAA, or TGA. By identifying the presence or absence of these codons in each sequence, we can make an informed decision.

Let's analyze each sequence:

Organism 1: GCCTAGGCATTACGCTACGTCGCATTATAC
Start codon: None
Stop codon: TAG (at the end)

Organism 2: GCTAAGGCACTACGCTACGTCGCTTAATAG
Start codon: None
Stop codon: TAG

Organism 3: GCTAAGCACTACGCTACGTCGCTTAATAGC
Start codon: None
Stop codon: TAG

Organism 4: GCTAAGGCACTACGCTACGTCGCATTATAC
Start codon: None
Stop codon: None

Organism 5: GCCAAGGCACTACGCTACGTCGCATTATAC
Start codon: None
Stop codon: None

Organism 6: GCTAAGGCACTACGCTACGTCGCTTTATAC
Start codon: None
Stop codon: None

Organism 7: GCTAAGAGACTACGGAACGCCGCTTAATAG
Start codon: None
Stop codon: TAG

Based on the analysis, we can see that Organisms 4, 5, 6, and 7 do not have a stop codon, which means the protein synthesis would continue indefinitely, and the sequence likely wouldn't lead to a functional part of a protein.

Therefore, Organism 4, GCTAAGGCACTACGCTACGTCGCATTATAC, is least likely to lead to a functional part of a protein.