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2.
When a teacher goes from being cool to not cool. Any kind of jumper or vest or bright colored blazer would be a symptom of crossing over
Mrs. Dante had the coolest shirt on yesterday and now she is wearing a jumper with letters all over it, she must have crossed over
by Harriet Potter September 23, 2004
 
1.
Genetics.
When genes croos over from.. UGH YOU WOULDN'T UNDERSTAND!
homoglobous chromosomes cross over
by AbsoluteR February 15, 2005