How many rounds of chromosome duplication and nuclear division does meiosis involve?

1. Meiosis has to cut the number of chromosome sets in half. 2. The DNA is copied once, during the S phase before meiosis begins. 3. Two nuclear divisions then follow that single copying step. 4. One copy shared over two divisions is what halves the chromosome sets and gives four cells. _Source: OpenStax Biology 1e (CC BY 4.0), Chs 10 and 11, section 11.1 The Process of Meiosis_