Gene Mutations and DNA Repair

A collection of vocabulary flashcards based on the concepts of gene mutations and DNA repair, designed to aid in exam preparation.

Lou Gehrig disease

A rare, progressive disease with features similar to frontotemporal dementia; about 10% of cases are familial.

Mutations

Inherited alterations in DNA sequence; sources of genetic variation and many diseases.

Somatic mutations

Mutations that occur in nonreproductive cells and are not passed to the next generation.

Germ-line mutations

Mutations that occur in cells that give rise to gametes and can be passed to the next generation.

Base substitutions

A type of gene mutation where one base is replaced by another, including transitions and transversions.

Frameshift mutations

Mutations that results from insertions or deletions, altering the reading frame of the gene.

Nonsense substitution

A mutation that changes a sense codon to a stop codon, leading to premature termination of translation.

Missense mutation

A mutation that causes a single amino acid change in the protein product.

Expanding nucleotide repeats

A type of mutation where the number of copies of a set of nucleotides increases.

Transposable elements

Sequences that can move around the genome; can cause mutations by inserting into genes or promoting rearrangements.

Mismatch repair

A DNA repair mechanism that corrects mismatches and lesions in DNA.

Nucleotide-excision repair

A repair mechanism that removes and replaces damaged DNA that distorts the helix.

Direct repair

Mechanism that restores altered nucleotides to their correct structures without excision.

Concept Check

Questions designed to assess understanding of key concepts presented.

Ames test

Test used to identify chemical mutagens by observing mutation rates in bacteria.

Buoyancy of mutations

Mutations are often detrimental but also necessary for evolutionary adaptations.