Now, we're going to assume we have a normal male individual and that means we have one X and we have one Y. Now, during interface we have replication taking place and so we produce this identical cystochromatid with respect to this one and this identical system chromatid with respect to this one. And if we fast forward to metaphase one of meiosis, we basically get these chromosomes line up the tetramer of chromosomes lineup at the equatorial plate. So once again, let's assume that nondisjunction takes place in anaphase two and not anaphase one. And so what that means is these mitotic spindle apparatuses or the spindle apparatus basically forms correctly and these fibers extend into onto these cystochromatid pairs and now segregation takes place and we form these two cells as shown. So these two haploid male cells and now once again, let's assume that nondisjunction took place during the second phase of meiosis.