Chapter 12 Flashcards
Wild type vs. Mutant phenotypes
Phenotype for a character most commonly observed in natural populations.
Alternative trait to wild type
Non wild= w,,,,,,, wild type=w+
Sex linked gene
A gene located on a sex chromosome
X linked genes
Gene located on the X chromosome; such genes show a distinctive pattern of inheritance
-father pass all x linked alleles to daughters but not sons. Mother can pass x linked alleles to both son and daughter.
Barr Body
A dense object lying along the inside of the nuclear envelope in cells of female mammals, representing a highly condensed, inactive, X chromosome.
(Reactivated in cells that give rise to eggs)
Linked genes
Genes located near each other on same chromosome tends to be inherited together.
Genetic recombination
The production of offspring with combinations of traits that differ from those found in the p generation parent.
Parental types
Recombinant type
An offspring with a phenotype that matches one or the true breeding parental phenotypes
Opposite
Genetic map
Linkage map
An ordered list of the genetic loci along a particular chromosome
A genetic map based on recombination frequencies.
Non disjunction
Members of a pair of homologous chromosomes do not move apart during meiosis 1 or sister chromatids fail to separate during meiosis 2.
Aneuploidy
Monosomic
Trisomic
Zygote with abnormal number of a particular chromosome
Zygote with missing chromosome
Zygote with more chromosomes
Polyploidy
Organisms with more than two complete chromosome sets
Strawberry=8n
Deletion
Chromosomal fragment is lost
Duplication
Fusion with a fragment from a homologous chromosome, such that a portion is duplicated
Inversion
Reattachment of a chromosomal fragment in a reverse orientation
Translocation
Movement of a segment of a chromosome to a non homologous chromosome
