Bivalents


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Related to Bivalents: bivalent chromosome

Bivalents

 

pairs of connected (conjugated) homologous chromosomes formed during nuclear division in meiosis. Chiasmas—X-shaped figures—are formed between chromosomes; they hold the chromosomes together within the complex. Genetic material may be exchanged at this time. The number of bivalents is normally equal to the number of chromosomes of the haploid (single) set.

References in periodicals archive ?
Identification of univalents and rod bivalents in Triticale with Giemsa.
1]-plants are possible; n bivalents and n univalents ([n.
Meiosis is achiasmatic; all bivalents are homomorphic, condensing gradually until metaphase I (Fig.
2b, 3a); meiosis is achiasmatic, and bivalents are homomorphic, condensing gradually during prophase I (Figs.
In the subphases prophase I and metaphases I, autosomal bivalents and the X univalent always occurred, even in the cells with 30 = 14II + 2X (Figs.
All bivalents present a ring shape, evidencing the occurrence of two terminal chiasmata per bivalent, and the X chromosome constitutes an univalent during all meiosis I (Fig.
More specifically, we observed two bivalents with two chiasmata in five diplotene nuclei and one bivalent with three chiasmata in five diplotene nuclei.