Question

Arrange the correct sequence of stages of Meiosis I:
A. Pachytene
B. Diplotene
C. Leptotene
D. Diakinesis
E. Zygotene
Choose the correct answer from the options given below:

• A. C, E, A, B, D
• B. A, E, B, C, D
• C. A, B, D, E, C
• D. A, B, C, E, D

Hint:

Mnemonic: “Little Zebra Paints Dark Designs” → Leptotene, Zygotene, Pachytene, Diplotene, Diakinesis.

Answer 1

The Correct Option is A

Step 1: Identify Prophase I substages.
Prophase I comprises Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis.
Step 2: Define each substage.
- Leptotene: Chromosome condensation begins.
- Zygotene: Homologous chromosomes synapse.
- Pachytene: Genetic material exchanges via crossing over.
- Diplotene: Homologous chromosomes separate, remaining connected at chiasmata.
- Diakinesis: Chromosomes reach maximum condensation, and the nuclear envelope disintegrates.
Step 3: Correlate with provided codes.
The correct sequence is C (Leptotene) → E (Zygotene) → A (Pachytene) → B (Diplotene) → D (Diakinesis).
Step 4: Evaluate choices.
Option (A) accurately represents this sequence.
Step 5: Final determination.
Consequently, the accurate order of Prophase I stages is Leptotene → Zygotene → Pachytene → Diplotene → Diakinesis.