A Single Base Substitution Mutation Is Likely to Have a Less

question 47

Multiple Choice

A single base substitution mutation is likely to have a less deleterious effect when the base change exhibits which of the following results?

• A) a stop codon
• B) a codon that specifies the same amino acid as the original codon
• C) an amino acid substitution that alters the tertiary structure of the protein
• D) an amino acid substitution at the active site of an enzyme

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Definitions:

Lac Operon

A gene regulatory mechanism in bacteria that controls the metabolism of lactose.

Rate of Transcription

The speed at which RNA polymerase produces RNA molecules from a DNA template, affecting gene expression.

DNA Methylation

A biochemical process involving the addition of a methyl group to the DNA molecule, often affecting gene expression and cellular function.

Gene Expression

The process by which information from a gene is used to synthesize functional gene products such as proteins, leading to the manifestation of the gene's effects.