DNA synthesis occurs during interphase before the beginning of meiosis I but does not occur again before meiosis II.

In prophase I, homologous chromosomes pair up into tetrads in a process called synapsis, and crossing over occurs, where genetic information is exchanged between nonsister chromatids of the homologues.

Crossing over produces recombinant chromosomes and contributes to genetic variation in sexual reproduction.

metaphase I