Meiosis question

[chiddler]

If nondisjunction occurs in meiosis II during gametogenesis, what will be the result at the completion of meiosis?

a. All the gametes will be diploid.
b. Two gametes will be n + 1, and two will be n - 1.
c. One gamete will be n + 1, one will be n - 1, and two will be n.
d. There will be three extra gametes.
e. Two of the four gametes will be haploid, and two will be diploid.

Answer is C but I can't figure out why B isn't the right answer.

my textual illustration:
normal cell (| |)

interphase before meiosis (X X), double DNA

meiosis begins, and synapsis happens (XX) so the homologous chromosomes join together

then normal meiosis I where the homologous chromosomes split apart into two separate cells (X) and (X)

then abnormal meiosis II, non-disjunction. (X), (nothing), (X), (nothing)

it looks like two cells are n+1 and two are n-1!

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[Episome]

This image correctly displays the two options for nondisjunction. Does this clear things up?

 

[cortana431]

Nondisjunction occurs only within 1 of the divided cells in Meiosis II. Not in both daughter cells in Meiosis II, which is what I think you're mistake is.

 

[chiddler]

thanks, makes perfect sense.