Question

Identify how mutations in genes and chromosomes can result from errors in DNA replication (point and frameshift mutation).

Options:
A) Mutations in genes and chromosomes only occur during transcription.
B) Errors in DNA replication can only lead to point mutations, not frameshift mutations.
C) Mutations in genes and chromosomes are unrelated to errors in DNA replication.
D) Errors in DNA replication can result in both point and frameshift mutations.

Answer 1

The correct answer is D, as errors during DNA replication can introduce both point mutations, which affect a single nucleotide, and frameshift mutations, which involve the insertion or deletion of nucleotides.

Step-by-step explanation:

The correct answer is D) Errors in DNA replication can result in both point and frameshift mutations.

Point mutations occur when there is a mistake that affects just one nucleotide pair in the DNA sequence. This might be a substitution of one base for another. For example, where the base sequence ACG might change to ATG, with T replacing C, altering the genetic code carried by that gene.

Frameshift mutations, on the other hand, are the addition or deletion of nucleotides that result in a shift of the reading frame of the genetic code. An example could be the insertion of an extra base in the sequence, such as ACG becoming AACG, or the deletion of a base, like ACG becoming AG, which can drastically alter the resulting protein synthesized from that DNA strand. Such mutations can have significant effects on an organism's phenotype and can be caused by slippage during DNA replication or by the influence of mutagens.

Mutations are a crucial source of genetic variation but can also lead to diseases if they disrupt the function of important genes. Considering this, the duplication and shuffling of genes during recombination, a separate aspect of genetic variation, play a significant role in evolution.