DEVELOPMENTAL PSYCHOLOGY
PRENATAL DEVELOPMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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When the corpus luteum degenerates
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During ovulation
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When it is penetrated by a sperm
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While waiting for the arrival of sperm in the Fallopian tube
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Detailed explanation-1: -Final answer: Meiotic division of the secondary oocyte completed at the time of fusion of a sperm with an ovum.
Detailed explanation-2: -The secondary oocyte completes its second meiotic division after a sperm has penetrated the secondary oocyte and sterilization has occurred. Therefore, the correct answer is A. When the secondary oocyte unites with sperm and becomes a zygote.
Detailed explanation-3: -If the secondary oocyte is fertilized by a sperm as it passes through the Fallopian tube, the secondary oocyte quickly completes meiosis II, forming a diploid zygote and another polar body. (This second polar body, like the first, normally breaks down and disappears.)
Detailed explanation-4: -Solution : The entry of sperm into the cytoplasm of ovum through zona pellucida and the plasma membrane induces the completion of meiotic division of secondary oocyte.
Detailed explanation-5: -The secondary oocyte begins the second meiotic division and then arrests again; it will not finish this division unless it is fertilized by a sperm; if this occurs, a mature ovum and another polar body is produced.