In each and every cell inside the nucleus There are copies of the chromosomes Our parents gave to us. And one set from dad Twenty-three in each set, two sets are what we have. But DNA will sometimes replicate Using one piece of chromatin for each template. That makes 4 sister chromatids in each tetrad. And they still stay that way.
Chromatin thickens into chromosomes And the nucleus fragments and the spindle forms.
Now spindle fibers bind to centromeres Metaphase lines up tetrads on the equator. And at random the homologues go separate ways. Go to opposite cell poles independently. That means the genome has been randomized DNA in the gametes Will be a surprise. But no way to predict how much of each you have.