Question

A DNA segment has base order CCC ATA GCT. Which copy exhibits a deletion in the first codon triplet and then a substitution mutation?(1 point) Responses CCA ATA GCT CCA ATA GCT CCA TAG CT CCA TAG CT CCA TAA CT CCA TAA CT CCC TAG CT

Answer 1

To analyze the given DNA segment "CCC ATA GCT," we need to break it down into codons (triplet bases). The first codon is "CCC."

1. **Deletion in the first codon triplet**: If we delete the first codon ("CCC"), we are left with "ATA GCT."

2. **Substitution mutation**: Now, we will substitute the first remaining base (A) of "ATA" for another base. The possible substitutions for A can be:
- C: CTC
- G: GTC
- T: TTA

Based on this, let's examine the choices for the mutated DNA sequence:

- **CCA ATA GCT**: This indicates the deletion of one C and not a complete codon deletion.
- **CCA TAG CT**: This indicates deleting part of the codon and not changing the second codon.
- **CCA TAA CT**: This indicates changing the second ask with a deletion.
- **CCC TAG CT**: This indicates changing A in third codon with C.
- **Other combinations** (like "CCC" being unchanged) don't apply.

Considering this analysis, the copy that best matches a deletion in the first codon triplet followed by a substitution mutation is:
**"CCA TAG CT"**

This indicates deletion of the first "C" and substitution of remaining bases.