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Prophase I:
- It is the typically longer and more complex.
- It includes 5 phases based on chromosomal behaviour:
Leptotene, Zygotene, Pachytene, Diplotene & Diakinesis.
Leptotene (Leptonema): Chromatin fibres become long slender chromosomes.
Nucleus enlarges.
Zygotene (Zygonema): Chromosomes become more condensed. Similar
chromosomes start pairing together (synapsis) with the help of a complex structure
called synaptonemal complex. The paired chromosomes are called homologous
chromosomes. Each pair of homologous chromosomes is called a bivalent.
