Question

Which stage represent transition to metaphase?

Answer 1

Answer:

At the metaphase to anaphase transition, the sister chromatids separate and move closer to the spindle poles (Anaphase A). During Anaphase B, the spindle poles move away from each other, thereby moving the chromosomes even further away from the plane of division, which will be at the spindle midzone.

Answer 2

The diakinesis stage of prophase-one marks the transition to metaphase during meiosis.

• The prophase one of meiosis consists of leptotene, zygotene, pachytene, diplotene and diakinesis.
• Genetic recombination occurs during pachytene, which attaches the chromosomes at the site of crossing over.
• During diplotene, the chromosomes un-attach themselves except at the sites of crossing over forming an X shaped chiasmata.
• Diakinesis or the final stage of Prophase one is characterised by dissolution of the chiasmata, assembling of meiotic spindle, breakdown of nuclear membrane and absence of nucleolus. This marks the transition from prophase to metaphase.