The diagram below shows spermatogenesis (on the left) and oo…

The diagram below shows spermatogenesis (on the left) and oogenesis (on the right) followed by a fertilization event.  The numbered circles are cells.  The long purple bars in the cells are X chromosomes while the short blue bars in the cells are Y chromosomes.  Bell #8 is the zygote resulting from fertilization.          a.  Where has the non-disjunction occur?  Use cell numbers to help you explain the location of the non-disjunction.       b.  What non-disjunction syndrome does this illustration demonstrate?  How do you know?