meiosis-help!

[jen]

im really bad at this topic and our school textbook doesnt provide us with much information.
there is a question i cannot do at all! it is:
What features of the preocess of meiosis ensure that the chromosome number of a species which reproduces sexually is maintained from generation to generation?
if anyone could help me out it would be greatly appreciated!
love jen

[opuntia]

Try this link...it might help you.
meiosis
Hope this helps

[Dr.Stein]

I will just give you a hint: non-disjunction