Question

The stage during which separation of the paired homologous chromosomes begins is

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

Answer 1

The Correct Option is C

The question pertains to the stages of meiosis in biology, specifically the separation of homologous chromosomes. Meiosis is a type of cell division that reduces the chromosome number by half and is essential for sexual reproduction. It consists of two stages: Meiosis I and Meiosis II. Each stage is further divided into several phases.

During Meiosis I, the homologous chromosomes separate. The prophase I of Meiosis I is divided into several sub-stages: Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis. Let's discuss the various stages to identify when the separation of homologous chromosomes begins:

1. Leptotene: Chromosomes start condensing but are not yet paired.
2. Zygotene: Synapsis begins with homologous chromosomes pairing along their lengths.
3. Pachytene: Crossing over occurs where genetic material is exchanged between homologous chromosomes, but they remain paired.
4. Diplotene: This is the stage where the synaptonemal complex begins to disassemble, and homologous chromosomes start to separate from each other except at the points of crossing over (chiasmata).
5. Diakinesis: The chromosomes condense further and prepare for metaphase. The separation progresses to culminate in metaphase I.

Based on the above detailed explanation, the correct stage where the separation of the paired homologous chromosomes begins is Diplotene.

Therefore, the correct answer is: Diplotene.