Question

Which best supports the choice from Questino 1?
Responses

A. Deletion mutations occur during DNA replication, changing how DNA is transcribed.

Deletion mutations occur when part of a DNA molecule is not copied properly during DNA replication. This leads to errors in the consecutive
processes of transcription and translation.
A. Deletion mutations occur during DNA replication, changing how DNA is transcribed. Deletion mutations occur when part of a DNA molecule is not copied properly during DNA replication. This leads to errors in the consecutive processes of transcription and translation.

B. Deletion mutations occur after DNA replication, changing how mRNA is translated.

Deletion mutations occur during, not after, DNA replication.
B. Deletion mutations occur after DNA replication, changing how mRNA is translated. Deletion mutations occur during, not after, DNA replication.

C. Deletion mutations occur during protein synthesis, changing the order of polypeptides.

Deletion mutations occur during DNA replication, not protein synthesis.
C. Deletion mutations occur during protein synthesis, changing the order of polypeptides. Deletion mutations occur during DNA replication, not protein synthesis.

D. Deletion mutations occur after protein synthesis, changing the proteins that are formed.

Deletion mutations occur during DNA replication, not after protein synthesis.

Answer 1

A.

Reason: A correctly states that deletion mutations happen when part of the DNA is not copied properly during DNA replication. That change in the DNA sequence is then transcribed into altered mRNA and can change the amino acid sequence produced during translation (often causing a frameshift if the number of bases deleted is not a multiple of three). Options B–D are wrong because they place the mutation after replication or during/after protein synthesis, whereas deletions originate in the DNA.