Question

In Meiosis-I, the pairing of homologous chromosomes take place during ___________
stage.
i) leptotene
ii) zygotene
iii) pachytene
iv) diplotene

Answer 1

The pairing of homologous chromosomes occurs during zygotene of prophase I of meiosis I.

During zygotene, chromosomes are visible as thin chromatin fibres.

These thin chromosomes appear paired with homologous chromosomes.

Every species starts their life cycle as the ovum with a single and complete set of that species.In subsequent pachytene phase, crossing over takes place between these homologous chromosomes leading to the formation of a bivalent and subsequently a synaptonemal complex.