How are meiosis I and meiosis II different

Meiosis I and meiosis II are two different parts of the meiosis cycle.

Meiosis I is similar to mitosis, where the DNA duplicates, arranges into two (full) sets of chromosomes, and then the cell divides.

With meiosis II, the DNA does not duplicate, but still the chromosomes are split in half again to create four sex cells. This ensures genetic variation by using 1/2 a set of chromosomes from each parent.