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Vocab 12.1
Chromosomes and Inheritance
Term | Definition |
---|---|
Sex Chromosome | One of the pair of chromosomes that determine the sex of an individual |
Autosome | Any chromosome that is not a sex chromosome |
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 |
Linked Gene | One of a pair of genes that tend to be inherited together |
Chromosome Map | A diagram of gene positions on a chromosome |
Map Unit | In Chromosome mapping, and increment of 1 percent in the freqeuncy of crossing-over |
Germ-Cell Mutation | Mutation that occurs in an organism's gametes |
Somatic-Cell Mutation | A mutation that occurs in a body cell |
Lethal Mutation | A gene or chromosomal mutation that influences the development of an organism in such a way that the organism cannot survive |
Deletion | The loss of a part of DNA from a chromosome |
Inversion | A reversal in the order of the genes, or of a chromosome segment, within chromosome |
Translocation | The movement of a segment of DNA from one chromosome to another, which results in a change in the position of the segment; also the movement of soluble nutrients from one part of a plant to another |
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 |
Substitution | A mutation in which a nucleotide or a codon in DNA is replaced with a different nucleotide |
Frameshift Mutation | A mutation, such as the insertion of 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 |
Insertion Mutation | A mutation in which one or more nucleotides are added to a gene |