What is the term for a heritable change in the DNA sequence?

• A. Mutation
• B. Genetic Drift
• C. Gene Flow
• D. Natural Selection

Answer: (A)

A heritable change in the DNA sequence is called a mutation. Mutations alter the genetic code by changing a base, adding or removing bases, or rearranging larger segments of DNA. When such changes occur in germ cells, they can be passed to offspring, providing new genetic variation for evolution.

Other terms refer to processes that modify how common different alleles are in a population but don’t describe the creation of new DNA sequences. Genetic drift involves random changes in allele frequencies, gene flow is the movement of alleles between populations, and natural selection is the differential survival and reproduction of individuals based on their genetic traits, which shifts allele frequencies over generations.