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Chp. 12, Section 1
Vocab for 12.1 Biology
Term | Definition |
---|---|
Autosome | Any chromosome that is not a sex chromosome |
Chromosome map | A diagram of gene positions on a chromosome |
Deletion | The loss of a part of DNA from a chromosome |
Frameshift mutation | A mutation, such as an insertion or deletion of a nucleotide in a coding sequence, that results in the misreading of the code during translation because of a change in the reading frame |
Germ-cell mutation | A mutation that occurs in an organism's gametes |
Insertion mutation | A mutation in which one or more nucleotides are added to a gene |
Inversion | A reversal in the order of the genes, or of a chromosome segment, within a chromosome |
Lethal mutation | A gene or chromosomal mutation that influences the development of an organism in such a way that the organism cannot survive |
Linked gene | One of a pair of genes that tend to be inherited together |
Map unit | In chromosome mapping, an increment of 1 percent in the frequency of crossing-over |
Nondisjunction | The failure of homologous chromosomes to separate during meiosis I or the failure of sister chromatids to separate during mitosis or meiosis II |
Point mutation | A mutation in which only one nucleotide or nitrogenous base in a gene is changed |
Sex-chromosome | One of the pair of chromosomes that determine the sex of an individual |
Sex-linked trait | A trait that is determined by a gene found on one of the sex chromosomes, such as the X chromosome or the Y chromosome in humans |
Somatic-cell mutation | A mutation that occurs in a body cell |
Substitution | A mutation in which a nucleotide or a codon in DNA is replaced with a different nucleotide |
Translocation | The movement of a segment of DNA from one chromosome to another, which results in a change in the position of the segment |