Diplotene

Diplotene is the stage in meiosis where the homologous chromosomes begin to separate. During this stage, the chromosomes start to condense and become visible under a microscope. One key event that occurs during diplotene is the formation of structures called chiasmata.

Chiasmata

Chiasmata are the cross-shaped structures that form between non-sister chromatids of homologous chromosomes during meiosis. These structures are the result of genetic recombination, where segments of DNA are exchanged between homologous chromosomes. Chiasmata play a crucial role in ensuring genetic diversity by shuffling genetic material between chromosomes.

Appearance in Diplotene

Chiasmata become visible during the diplotene stage of meiosis. As the homologous chromosomes start to separate, the chiasmata can be seen holding the chromosomes together at the points where genetic material has been exchanged. The presence of chiasmata is a key indicator that genetic recombination has occurred and that the process of meiosis is proceeding correctly.

In conclusion, chiasmata appear in the diplotene stage of meiosis. They are important structures that facilitate genetic recombination and contribute to genetic diversity.