Two homologous chromosomes that are paired together during the first division of meiosis.
The structure formed when a pair of homologous chromosomes lines up during meiosis.
A pair of synapsed or associated homologous chromosomes (one of maternal origin; the other of paternal origin) that have each undergone duplication. Each duplicated chromosome comprises two chromatids. Thus a bivalent comprises four chromatids.-lactamase An ampicillin resistance gene. See selectable marker.
a pair of homologous, synapsed chromosomes
A pair of homologous chromosomes closely adjacent to each other formed during the first meiotic division within a primary spermatocyte or oocyte.
A physical connection between homologous chromosomes that forms during meiosis. Crossing over takes place when the chromosomes are in this orientation.
Structure, formed during prophase of meiosis 1, consisting of synapsed homologous chromosomes. Equivalent to a tetrad of chromatids.
two synapsed chromosomes in prophase I of meiosis.
A bivalent is sometimes referred to as a tetrad.