Prophase I : The exchange of genetic material between non-sister chromatids of homologous chromosomes occurs. This process is called crossing over. At the end of this phase, the chromosomes condense completely and the nuclear membrane and nucleolus disappear.
Metaphase I : The chromosomes align along the metaphase plate and the spindle fibres from opposite poles attach to the homologous chromosomes.
Anaphase I : The homologous chromosomes separate but the sister chromatids remain intact.
Telophase I : The nuclear memebrane and nucleolus reappear, cytokinesis occurs and two daughter haploid cells called dyad of cells is formed.