Final answer:
Homologous recombination (HR) is completed through the process of crossing over during meiosis. This involves the exchange of genetic material between non-sister chromatids of homologous chromosomes. The synaptonemal complex and recombination nodules facilitate this process.
Step-by-step explanation:
Homologous recombination (HR) is completed through the process of crossing over during meiosis. Crossing over occurs during prophase I, where genetic material is exchanged between non-sister chromatids of homologous chromosomes. This exchange of genetic material can happen multiple times within the same pair of homologous chromosomes, creating unique combinations of genes. The synaptonemal complex and recombination nodules play important roles in facilitating the formation of chiasmata, which are physical connections between homologous chromosomes that mark the sites of crossover.