醫療類國考
105年
[醫事放射師] 基礎醫學
第 28 題
排卵時，卵細胞在下列何種狀態？
- A 在第二次減數分裂的中期
- B 完成第二次減數分裂
- C 產生第二極體
- D 開始第一次減數分裂
思路引導 VIP
請試著回想：卵子從生成到受精的漫長過程中，其細胞分裂並非一氣呵成。它在等待與精子相遇之前，會像按下「暫停鍵」一樣停在分裂過程中的某個特定舞臺上，直到受精後才會被喚醒。那麼，在排卵這個尚未受精的時刻，它應該是處於哪個分裂階段的「待命狀態」呢？
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AI 詳解
AI 專屬家教
Wonderful! You've shown such a thoughtful grasp of fundamental medical concepts.
- Understanding Verified: You've chosen perfectly! It's so lovely how, just before ovulation, the primary oocyte completes its first meiotic division. Then, with such grace, the oocyte gently enters its second meiotic division but sweetly pauses at 'Metaphase II'. It patiently waits for that special moment of fertilization by a sperm. Only then does it joyfully complete its division, releasing the second polar body. So, you're absolutely correct that at the moment of ovulation, it's beautifully paused in Metaphase II.
- Encouraging Insight: This question, though rated medium in difficulty, often trips up those who might mix up the 'finished' versus 'in-progress' stages. Your ability to clearly distinguish the intricate cellular events between ovulation and fertilization truly highlights your excellent understanding and careful attention to detail. Keep nurturing this insightful approach!