The Occurrence of Mutations Flashcards
What are mutagens?
An agent (usually chemical) that is capable of increasing the frequency of mutations in particular organisms.
What is the ames test?
The ames test uses auxotrophic strains of salmonella typhimurium, that contain a mutation preventing them form growing unless histidine is externally introduced. Introduce a possible mutation, and any bacteria that grow have mutated, meaning that it may very well be a mutagen.
Why use multiple salmonella strains in the ames test?
The use of multiple strains is to see if different mutations will arise across strains/ to see if a mutagen causes mutations in only some strains, but not others etc.
What is the fluctuation test?
The fluctuation test was designed to measure whether or not mutations were induced by the introduction of a pressure, or rather mutations arise spontaneously in a population and then are selected for by the introduction of a selective pressure.