(a) Synapsis : It is the pairing of homologous chromosomes at cell division. It occurs in Zygonema.
(b) Bivalent: Complex formed by a pair of synapsed homologous chromosomes is called a bivalent. It is also known as a tetrad.
(c) Chiasmata: The points of crossing of two non-sister
chromatids. It is X-shaped point of interchange of chromosomes