During diplotene (Gr. diplous = in twofold) it becomes clearly visible that each replicated chromosome consists of two sister-chromatides. Each bivalent consist of a bundle of four homolog chromatides. Homologs exhibit a weaker binding and slightly diverge. The crossings (= chiasmata; singular chiasma, named after the cross-shaped lgreek letter chi) between non-sister-chromatides are visible. Each bivalent shows in general one or more chiasmata, where crossing-overs have occured.
