The meiosis model contains 9 models. The 1st and 2nd modelsshow there are homologous chromosomes changing, which is the1st division of meiosis. The 3rd model shows chromosomespairing but cannot tell sister chromatid, which is meiosis jointperiod. In the 4th model, 4 chromatids can be seen in the pairedchromosomes, which is four division period of meiosis. In 5thmodel, centromeres are located near two sides of metaphaseplate which means tetrad are on the metaphase plate, which ismiddle period of meiosis I. In 6th model, centromeres move tothe two poles from the metaphase plate, which is anterior periodof meiosis I. In 7th model, centromeres which are not on themetaphase plate begin to be lined on the plate, which ispre-period and mid-period of meiosis II. In the 8th model, the newtwo nucleus are not formed yet, which is anterior period ofmeiosis. In the 9th model, the two nucleus have been formedwhich is the end period of meiosis.