Ch. 5.5- Three main categories of mutation Flashcards
Define mutation
A change in the genetic material of a cell or virus.
Define substitution mutation
Occurs when an incorrect nucleotide is added.
Define insertion mutations
Occurs when a cell adds one or more nucleotides to its genome sequence.
Define deletion mutation
Occurs when one or more nucleotides are removed from a genome sequence.
Define a silent mutation
A form of substitution mutation where the resulting protein is the same as it would have been prior to mutation.
Define a missense mutation
A form of substitution mutation where the new codon encodes the wrong amino acid.
Define a nonsense mutation
A form of substitution mutation where the change in codon leads to a stop signal instead of the production of an amino acid.
Define reversion mutation
When a base substitution is made, and then another base substitution occurs that brings the codon back to its original state.
Define a frameshift mutation
When a base is inserted or deleted from the codon- often leading to a useless protein.
Define spontaneous mutations
Mutations that occur naturally.
Define a “wild type”
Non-mutated base pairs
Define mutagen
Chemical, physical, or biological agents that increase the rate of mutation
Define recombination
Done by biological mutagen that encourages the exchange of genetic materials and leads to new genetic combinations
Define cancinogens
Cause a rate of mutation that promotes the development of cancer.
Define ames test
This test quickly identifies mutagens that alter DNA by base substitution or frameshift mutation.
