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 | pairs of genes that tend to be inherited together |
chromosome map | a diagram of gene positions on a chromosome |
map unit | a frequency of crossing over of 1% |
germ-cell mutation | mutation that occurs in an organisms gamete; Don't affect the organism itself, but may be passed on to offspring |
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 f a chromosome segment, within a 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 1 or the failure of sister chromatids to separate during mitosis or meiosis 2 |
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 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 |
insertion mutation | One or more nucleotides are added to a gene, which also results in a frameshift mutation |