Sources of Genetic Variability in Sexually Reproducing Organisms
What produces genetic variety in groups of organisms that reproduce sexually?
The chromosomes independently line up and come together during Metaphase I. This is called Independent Assortment.
(The positioning of each homologous chromosome at Metaphase I is totally a matter of chance. Tetrads are assembled randomly AND the orientation of one tetrad does not impact the orientation of another tetrad.)