Question

Chiasmata formation occurs during which sub-stage of meiosis?

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

Hint:

Remember: Crossing over happens in pachytene, but \textbf{chiasmata become visible} in diplotene — think "D" for Diplotene and Display.

Answer 1

The Correct Option is B

Chiasmata are the visible manifestations of crossing over between homologous chromosomes, and they become apparent during the diplotene stage of prophase I of meiosis.

• During leptotene, chromosomes begin to condense.
• In zygotene, homologous chromosomes begin pairing (synapsis).
• Pachytene is when crossing over occurs.
• Diplotene is when the synaptonemal complex dissolves and chiasmata become visible — correct stage.