The process by which a diploid (2n) cell forms four haploid (1n) gametes. Meiosis differs from mitosis as meiosis I involves chromosomal content being recombinantly halved.
Leptotene. Chromosomes organise axial elements and acquire recombination proteins. Homologues pair ready for synapsis.
Zygotene. Crossing over sites are designated, chromosomes begin and complete synapsis. Axial elements align to form synaptonemal complex.
Pachytene. Chromosomes are thicker due to pairing and contraction.
Diplotene. Synaptonemal complex degrades and 4 chromatids become visible. In some organisms (such as goats) this stage is prolonged into dictyotene.
Diakinesis. Chromosomes continue to thicken due to coiling, nuclear envelop disappears, kinetochores and spindle develop.
Bivalents line up along equator of spindle, attached to centromeres.
unlike mitosis, centromeres do not divide.
This page was last modified on 5 November 2018, at 17:27.