A DNA segment has base order CCC ATA GCT. Which copy exhibits a deletion in the first codon triplet and then a substitution mutation?
A) CCA TAG CT
B) CCA ATA GCT
C) CCC TAG CT
D) CCA TAA CT
The correct answer is B) CCA ATA GCT.
Explanation:
A deletion mutation involves the loss of one or more nucleotides, leading to a shorter DNA sequence. In this case, the first codon triplet "CCC" is deleted, resulting in a shorter DNA sequence that starts with "CCA."
A substitution mutation involves the replacement of one nucleotide with another. In this case, the second codon triplet "ATA" is changed to "TAG."
Therefore, the correct answer is B) CCA ATA GCT, which exhibits a deletion in the first codon triplet and a substitution mutation in the second codon triplet.