In the human ovary, the primary oocyte remains arrested in meiotic prophase I from fetal life until ovulation. At which specific stage of meiosis is this arrest maintained?
- A Leptotene stage
- B Diplotene stage of prophase I ✓
- C Zygotene stage
- D Metaphase II
Correct answer: B. Diplotene stage of prophase I
Explanation
The primary oocyte is arrested in the diplotene stage of prophase I (also called the germinal vesicle stage) from fetal life until the LH surge triggers resumption of meiosis before ovulation. Metaphase II arrest occurs only after fertilization. This prolonged arrest is unique to oocytes and can last decades.
Reference: Boron and Boulpaep Medical Physiology, 3rd ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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