A sector of a DivA strang is snown.

Question

5'-AT CG C C GAT A C T-3'
Which replicated DNA strand experienced a single substitution mutation during replication?
A 3'-TAGCGG C TAT CA-5'
⑥ 3'-TAAGCGGCTATGA-5'
© 3'-TAGCGGCTATGATGA-5'
D 3'-TAGGGCTATGA -5'A sector of a DivA strang is snown.

5'-AT CG C C GAT A C T-3'
Which replicated DNA strand experienced a single substitution mutation during replication?
A 3'-TAGCGG C TAT CA-5'
⑥ 3'-TAAGCGGCTATGA-5'
© 3'-TAGCGGCTATGATGA-5'
D 3'-TAGGGCTATGA -5'

Answer 1

To determine which replicated DNA strand experienced a single substitution mutation, we first need to identify the complementary strand of the given DNA template. The original sequence provided is:

5'-ATCGCCGATACCT-3'

The complementary strand (which would be replicated from the template) would be:

3'-TAGCGGCTATGGA-5'

Now, let's analyze each option to see which contains a single substitution mutation when compared to the expected complementary strand.

• A) 3'-TAGCGGCTATCA-5'

  • This differs from the expected strand by replacing 'GGA' with 'CA'. However, this is two substitutions, so it's not a single substitution mutation.

• B) 3'-TAAGCGGCTATGA-5'

  • This strand has 'TAG' changed to 'TAA' and 'GGA' changed to 'GA', which is also not a single substitution mutation.

• C) 3'-TAGCGGCTATGATGA-5'

  • This strand has 'GGA' changed to 'GATGA', but that is more than one substitution as well.

• D) 3'-TAGGGCTATGA-5'

  • Here, the original 'GGA' was changed to 'GG' which means one nucleotide ('A') has been substituted to 'G'.

The only option that represents a single substitution is D (3'-TAGGGCTATGA-5') where a single nucleotide was substituted (A to G).

Thus, the correct answer is:

D 3'-TAGGGCTATGA-5'