So what that means is the following. So this diagram generalizes the process of meiosis one. So let's suppose we begin with a cell that consists of a single pair of homologous chromosomes shown in the following diagram. So we have pair one or chromosome one and chromosome two. So during ProPhase one of meiosis, this homologous pair undergoes the process of crossing over, and we basically form these recombinant chromosomes. And what that basically means is each one of these chromatids are genetically different than the other one.