THE CORE. “In eukaryotic sexual life cycles, haploid cells fuse to give rise to diploids, before diploid cells are converted back to haploids in a process known as meiosis. Meiosis reduces a cells chromosome number by half, whilst also creating new allele combinations distributed across daughter cells through segregation and recombination.”
http://biorxiv.org/content/biorxiv/early/2016/04/28/050831.full.pdf