Synaptonemal Complex
From The School of Biomedical Sciences Wiki
The synaptonemal complex is a protein which forms between homolgous chromosomes. The synaptonemal complex begins to form during the zygotene phase of Prophase I in Meiosis and is complete in the pachytene phase. Acting like a 'zipper' it holds the homologous chromosomes together, aligning them perfectly. After complete synapsis, crossing over occurs and in the diplotene phase, where the chiasma is visible, the synaptonemal complex 'unzips' and disappears.
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