|MadSci Network: Genetics|
Fertilization is the process by which two haploid cells, called gametes, fuse to form a diploid zygote, technically defined as syngamy. The mechanism of syngamy is essentially the opposite of meiosis, whereby diploid cells divide to become haploid gametes.
Probably the reason that your professor didn't know much about the mechanism of chromosomal pairing during fertilization is that there doesn't seem to be a lot of detailed information available. The section entitled The Sperm Provides a Centriole for the Zygote, from the chapter on "Fertilization" in Molecular Biology of the Cell @ NCBI, explains an interesting aspect of chromosome pairing during syngamy, with a helpful Figure as well.
This textbook also references 2 review articles, Molecular Basis of Fertilization and Early Events in Mammalian Fertilization, which I didn't have a chance to look at but would probably explain more of the details, if you're interested.
It's clear that there are certainly some complex events that do occur during syngamic chromosome pairing, but I was fairly disappointed at not being able to come up with a more detailed molecular description for you.
Thank you very much for the nonetheless excellent question,
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