DNA contains a code for synthesizing proteins. Three nucleotides in a row code for a particular amino acid. There are four nucleotides in DNA, which are abbreviated as A,T,C,G. The amino acids are joined to form a protein. Genetic mutations can occur in the DNA of individuals. Some mutations are harmful, some have no effect, and some might be beneficial to the organism. The table shows the nucleotide sequence of DNA that codes for a protein in one individual and the nucleotide sequence of the same segment of DNA in an individual with a mutation.

Which statement describes the most likely impact of the mutation in the mutated sequence?

(1 point)
Responses

The mutated DNA will code for the same number of amino acids as the original sequence.
The mutated DNA will code for the same number of amino acids as the original sequence.

There will be no effect because the rest of the DNA is normal.
There will be no effect because the rest of the DNA is normal.

The protein formed will not be the same as that formed from the original DNA sequence.
The protein formed will not be the same as that formed from the original DNA sequence.

The extra nucleotide will be deleted before the protein is formed.
The extra nucleotide will be deleted before the protein is formed.

1 answer

To determine the impact of the mutation in the DNA sequence, we need to consider that mutations can lead to changes in the amino acid sequence of the protein that is produced, depending on the nature of the mutation (e.g., whether it is a substitution, insertion, or deletion).

Given the options provided:

  1. The mutated DNA will code for the same number of amino acids as the original sequence. - This may be true if the mutation is a silent mutation or another type that does not change the reading frame or total number of amino acids coded, but it is not guaranteed.

  2. There will be no effect because the rest of the DNA is normal. - This is misleading; even a single change can have an effect if it alters the codons that specify amino acids.

  3. The protein formed will not be the same as that formed from the original DNA sequence. - If the mutation changes one or more codons, it is likely that the resulting protein will be different in amino acid sequence, potentially affecting its function.

  4. The extra nucleotide will be deleted before the protein is formed. - This is unlikely unless there is a specific mechanism in place to remove extra nucleotides, which is not a standard process for most mutations.

Based on the potential for mutations to have a significant impact on the resulting protein, the most appropriate statement would be:

The protein formed will not be the same as that formed from the original DNA sequence.