Question

Dissolution of the synaptonemal complex occurs during which of the following stages?

• A. Diplotene
• B. Leptotene
• C. Pachytene
• D. Zygotene

Answer 1

The correct option is A Diplotene

The prophase stage of meiosis I (or prophase I) is divided into five stages which include leptotene, zygotene, pachytene, diplotene and diakinesis.

• Leptotene is characterised by gradual condensation of chromosomes.
• Zygotene is characterised by the pairing of homologous chromosomes, called synapsis, accompanied with formation of the synaptonemal complex.
• Pachytene is the stage in which exchange of segments of non-sister chromatids of homologous chromosomes occurs.
• Diplotene is characterised by the dissolution of the synaptonemal complex. The recombined homologous chromosomes start separating except at the crossover sites giving rise to X-shaped structures called chiasmata.
• Diakinesis is marked by the terminalisation of chiasmata. Nuclear membrane and nucleolus completely disappear by the end of this phase.