In a process called Synapsis, paired homologous chromosomes align randomly at the cell equator. This occurs during stage prophase I of cell division.
Synapsis refers to the pairing of the homologous chromosomes in the meiosis occuring in the reproductive cells. Meiosis I is divided into four phases called the prophase I, metaphase I, anaphase I and the telophase I. Prophase I is the longest phase of meiosis which is further divided into leptotene, zygotene, pachytene, diplotene and diakinesis.
During the zygotene of meiosis I, the paring of the homologous chromosomes called the synapsis takesplace which is facilitated by the protein structure called the synaptonemal complex. The paired chromosomes are called the bivalents. This facilitates the homologous recombination.