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    I'm a bit confused, its says that when the sperm and egg fuse to form a zygote. But then they add that the 2 nuclei don't fuse immediately instead the cell divides by mitosis to begin zygote formation. What gives?
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    (Original post by Mr Burns)
    I'm a bit confused, its says that when the sperm and egg fuse to form a zygote. But then they add that the 2 nuclei don't fuse immediately instead the cell divides by mitosis to begin zygote formation. What gives?
    The two pro-nuclei don't really fuse as such - they just enter mitosis together.

    The cytoplasm etc fuses, so the initial zygote will have two pro-nuclei.
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    (Original post by Asklepios)
    The two pro-nuclei don't really fuse as such - they just enter mitosis together.

    The cytoplasm etc fuses, so the initial zygote will have two pro-nuclei.
    All right, out of curiosity when does it happen then?
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    (Original post by Mr Burns)
    All right, out of curiosity when does it happen then?
    Well roughly:

    - sperm and oocyte fuse to form a zygote with two pro-nuclei
    - DNA replication in each pro-nuclei
    - Each pro-nuclei undergoes prophase separately
    - The nuclear envelopes then disappear and all the chromosomes from both male and female pro-nuclei line up on the metaphse plate
    - Rest of mitosis as normal
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    (Original post by Asklepios)
    Well roughly:

    - sperm and oocyte fuse to form a zygote with two pro-nuclei
    - DNA replication in each pro-nuclei
    - Each pro-nuclei undergoes prophase separately
    - The nuclear envelopes then disappear and all the chromosomes from both male and female pro-nuclei line up on the metaphse plate
    - Rest of mitosis as normal
    Thanks! It's a bit had to remember because I can't even imagine mitosis of haploid nuclei, new concept I guess. Have an upvote for your help!
 
 
 
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