Mutations Flashcards
Mutation
Small permanent change in the DNA of an organism.
Point Mutation
A change in a single nucleotide in the DNA code that may result in translation of one different amino acid in a polypeptide sequence.
Somatic Mutation
A mutation in the somatic tissue of an organism that affects the specific cell type but is not inherited.
Germline Mutation
A heritable change in the DNA that occurs in a germ cell (a cell destined to become an egg or sperm) or the zygote at the single-cell stage and is also incorporated in every cell of the body.
Frameshift Mutation
The deletion or insertion of a single or non-multiple of three nucleotides into the DNA.
Chromosome Mutation
A change in the chromosome structure or number, often due to an error in pairing during the crossing over stage of meiosis.
Homologos
Two chromosomes that are homologous; during meiosis, the set of paring maternal and paternal chromosomes have the same genes at the same loci but may have different alleles.
Chromosome Deletion
Loss of a part of a chromosome during DNA replication.
Duplication
Any repetition of a region of DNA that contains one or more genes.
Translocation
Movement of a chromosomal segment from one position to another, either within the same chromosome or to another chromosome.
Inversion
A chromosome rearrangement in which a segment of chromosome is reversed end to end.
Nondisjunction
The failure of homologous chromosomes or sister chromatids to separate during meiosis.
Aneuploidy
Presence of an abnormal number of chromosomes in a cell.
Autosomal Aneuploidy
Presence of an abnormal number of autosomal chromosomes.
Sexual Aneuploidy
Presence of an abnormal number of sex chromosomes in a sex cell.
Trisomy
Occurs when a diploid organism has three copies of one of its chromosomes instead of two.
Karyotype
The number and visual appearance of the chromosomes in the cell nuclei of an organism or species.
Hereditary Mutation
Gene change in a body’s reproductive cell that can be passed from parent to offspring.
Somatic
Non-reproductive.
Mutagen
A physical or chemical agent that changes the genetic material of an organism.
Carcinogen
A substance or agent that can cause cells to become cancerous by altering their genetic structure so that they multiply continually and become malignant.
