chromatin strands condense, the homologous chromosomes pair
up, side by side, lying together in perfect alignment during a process called synapsis, this pairing of homologous chromosomes is an important part of the cell
cycle. Chiasmata (chiasma) forms, a cross-shaped structure where the
homologous chromosomes attached forming a bivalent. A bivalent indicates 2 homologous chromosomes in the unit (or a tetrad of 4 chromatids in the unit). Each chiasmata indicates a point at which the homologues exchange genetic material between non-sister chromatids, a process called "crossing over" or "recombination,"
-5 stages: leptotene, zygotene, Pachytene (recombination), diplotene (homologs separate, remain attached at chiasmata), diakinesis