Meiosis is the reductional division and half the genetic make-up is the resultant of this type of cellular division. This is a phenomenon seen during the production of gametes as the combination of two halves of the genetic makeup of two individuals during sexual reproduction will give rise to an organism. One of the benefits of sexual reproduction is the diversity it produces within a population. That variety is a direct product of meiosis. Every sex cell made from meiosis has a unique combination of chromosomes. This means that no two sperm or egg cells are genetically identical.