In oocytes of some vertebrates, diplotene lasts for months or years. It is called

Answer

**Step-by-Step Solution:**

1. **Understanding Oocytes**: Oocytes are the female gametes or eggs in vertebrates. They undergo a process called oogenesis, which includes several stages of development.

2. **Meiosis in Oocytes**: During oogenesis, oocytes undergo meiosis, which is a type of cell division that reduces the chromosome number by half. Meiosis has several stages, including prophase, metaphase, anaphase, and telophase.

3. **Diplotene Stage**: The diplotene stage is a specific phase within prophase I of meiosis. It is characterized by the pairing of homologous chromosomes and the beginning of their separation.

4. **Duration of Diplotene**: In some vertebrates, the diplotene stage can last for an extended period, ranging from months to years. This prolonged duration is significant in the development of oocytes.

5. **Term for Extended Diplotene**: The prolonged diplotene stage in oocytes is referred to as the "dictyate stage" or "diplotene arrest." During this time, the oocytes remain in a suspended state until they are triggered to continue development, often at puberty in females.

6. **Conclusion**: Therefore, the answer to the question is that the diplotene stage lasting for months or years in oocytes of some vertebrates is called the "dictyate stage."

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