If an organism has a diploid number, i.e. 2n = 16, it has n = 8 pairs of homologous chromosomes. Each chromosome has 2 chromatids. Prophase = coiling up of DNA, making it visible. There is no replication of DNA during prophase. As such, during the mitotic prophase, you'd see 2 x 8 = 16 chromatids. Anaphase = separation of chromatids. Again, there is no replication of DNA. Half of the total chromatids move to each pole. Each chromatid here is considered 1 chromosome. Since we started with 16 chromatids, 8 chromosomes will be moving to each pole.
