Final answer:
A point mutation involves a change of just one base in the DNA sequence. It can lead to silent, missense, or nonsense outcomes, depending on how the base change affects the codon. The correct answer to the given question is c) Point.
Step-by-step explanation:
A point mutation refers to a mutation in which just one base is changed within the DNA sequence. This type of mutation can lead to different outcomes depending on the nature of the base change. The three types of point mutations include:
- Silent mutation: A change in the nucleotide sequence that does not alter the amino acid that is produced, so there is no change in the phenotype.
- Missense mutation: A nucleotide change that alters the amino acid sequence of a protein, leading to a potential change in protein function.
- Nonsense mutation: This change creates a premature stop codon within the sequence, leading to an incomplete, usually nonfunctional protein.
A frameshift mutation, by contrast, is not a point mutation. It involves the insertion or deletion of one or more nucleotides, which shifts the reading frame of the DNA sequence. This can lead to widespread changes in the resulting amino acid sequence.
Based on this information, the correct answer to the student's question, "A(n) _____ mutation refers to a mutation in which just one base is changed within the DNA sequence," is c) Point.