Meiotic division of the secondary oocyte is completed
- At the time of fusion of a sperm with an ovum
- At the time of copulation
- Prior to ovulation
- After zygote formation
Answer
(1) At the time of fusion of a sperm with an ovum
Solution
As per NCERT, the ovum is released from the Graafian follicle as a secondary oocyte (arrested in meiosis II).
The entry of the sperm into the ovum induces completion of the meiotic division of the secondary oocyte, which forms the haploid ovum (ootid) and the second polar body; the haploid nuclei of sperm and ovum then fuse to form the diploid zygote.
∴ Meiosis II is completed at the time of fusion of a sperm with the ovum.
Answer: (1)