Meiosis II and mitosis are similar in that both processes involve the separation of attached, duplicated chromosomes, called sister chromatids, into daughter cells, explains University of Illinois at Chicago. While meiosis I is a reductive division, meiosis II and mitosis are equatorial divisions, notes Boundless.
Mitosis is the biological process by which non-reproductive body cells, called somatic cells, replicate and divide, while meiosis creates sperm and egg cells, called gametes, to be used in sexual reproduction, notes University of Illinois at Chicago. In most animals and plants, mitosis produces two identical diploid cells, and meiosis creates four genetically unique haploid cells, explains Boundless. A diploid cell possesses two copies of each chromosome, while a haploid cell possesses only one of each chromosome. During sexual reproduction, haploid sperm and egg cells combine to form a diploid zygote, notes UIC.
During meiosis I, pairs of homologous chromosomes line up and separate to reduce the number of chromosomes in each daughter cell by half, explains UIC. Each homologous pair consists of two copies of each chromosome, one inherited from the maternal parent and the other from the paternal parent. At this stage, the chromosomes are in their duplicated state, consisting of attached sister chromatids. Since this phase reduces the number of chromosomes, it is considered a reductive division.
In both meiosis II and mitosis, the attached sister chromatids of each chromosome split at their attachment points, called centromeres, notes UIC. This is called an equatorial division since it reduces the amount of DNA present in each cell rather than the number of chromosomes, explains Boundless.