Synapsis holds pairs of homologous chromosomes together
Early in prophase I, homologous chromosomes come together to form a synapse. The chromosomes are bound tightly together and in perfect alignment by a protein lattice called a synaptonemal complex and by cohesin proteins at the centromere.
Source
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"OpenStax College, The Process of Meiosis. October 16, 2013."
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OpenStax CNX
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