AAMC qpack question-SPOILER

[lebronthegoat]

I do not understand this question if anybody could plz explain it to me
If chromosomal duplication before tetrad formation occurred twice during spermatogenesis, while the other steps of meiosis proceeded normally, which of the following would result from a single spermatocyte?
The answer is four diploid sperm

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[numdane_usermane]

So tetrad formation is when the homologous chromosomes come together. The question says that the chromosomes duplicate in the original spermatocyte and so you have 2 times the amount of chromosomes that a typical spermatocyte would have. The cell then undergoes its rounds of meiosis, and with a normal amount of chromosomes, the cell should end up with 4 haploid sperm, right? However, there is double the amount of chromosomes from the start and the cell cannot undergo an additional round of meiosis to make 8 haploid sperm. So instead you get 4 diploid sperm to evenly spread out the additional chromosomes.

Hope that made sense!

 

[lebronthegoat]

So tetrad formation is when the homologous chromosomes come together. The question says that the chromosomes duplicate in the original spermatocyte and so you have 2 times the amount of chromosomes that a typical spermatocyte would have. The cell then undergoes its rounds of meiosis, and with a normal amount of chromosomes, the cell should end up with 4 haploid sperm, right? However, there is double the amount of chromosomes from the start and the cell cannot undergo an additional round of meiosis to make 8 haploid sperm. So instead you get 4 diploid sperm to evenly spread out the additional chromosomes.

Hope that made sense!

that definitely helped thanks alot!