Prophase I of meiosis is divided into five substages.
- In Leptonema (Lepto: thin),
the replicated chromosomes begin to condense at areas called
chromomeres.
Also, homologous chromosomes begin to find each other in a process called homology search.
- In Zygonema (Zygo: pair),
the chromosomes continue to condense,
and homologous chromosomes undergo loose alignments with each other,
forming
bivalents, each of which contains four chromatids, though the individual chromatid
are yet visible at this substage.
continue