17 terms

Ch. 15 The Chromosomal Basis of Inheritance

chromosome theory of inheritance
the behavior of chromosomes during meiosis and fertilization accounts for inheritance patterns
genetic recombination
the production of offspring with combinations of traits differing form those found in either parent
crossing over
accounts for the recombination of linked genes. occurs during prophase of meiosis I.
genetic map
an ordered list of the genetic loci along a particular chromosome
linkage map
a genetic map based on recombination frequencies
cytogenetic maps
locate genes with respect to chromosomal features
sex-linked gene
a gene located on a sex chromosome
members of a pair of homologous chromosomes do not move apart properly during meiosis I or sister chromatids fail to separate during meiosis II
offspring has an abnormal number of a particular chromosome
having three copies of a chromosome
Referring to a cell that has only one copy of a particular chromosome, instead of the normal two.
organisms that have more than two complete chromosome sets
occus when a chromosomal fragment lacking a centromere is lost
when a deleted fragment becomes attached to a sister chromatid
chromosomal fragment is reattached to the original chromosome
fragment joins a nonhomologous chromosome
genomic imprinting
The parental effect on gene expression whereby identical alleles have different effects on offspring, depending on whether they arrive in the zygote via the ovum or via the sperm.