In diplotene the pairs of chromatids begin to separate from the tetrad formed by the association of homologous chromosomes.

双线期时，配对的染色单体开始从四分体中分离，此时常可见染色体交叉。

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Synapsis (pairing) the association of homologous chromosomes during the prophase stage of meiosis that leads to the production of a haploid number of bivalents.

偶线期时，以同源染色体活跃的、特定的配对(联会)为特征，形成了单倍数的二价染色体。

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