Zygotene Locusta migratoria Lilium grandiflorum Petunia hybrida At zygotene (Gr. zygon = touching another), the stage after leptotene, the pairing of the homolog chromosomes (synapsis) begins. The homolog chromosomes are hold together by proteins (synaptomal complex). Next, crossing-over can happen between the DNA-double helices molecules of homolog chromosomes.

http://www.vcbio.science.ru.nl/en/virtuallessons/cellcycle/meiostage/zygotene/print/