Grades of chromatid organisation in mitotic and meiotic chromosomes

It is suggested that not one, but four different grades of lampbrush chromosome organisation characterise different stages of mitosis and meiosis: (a) where a single chromatid organises symmetrically disposed lateral loops (second meiotic prophase), (b) where the two sister chromatids of a visibly single chromosome organise lateral loops in a laterally asymmetrical fashion, both sets of loops projecting from the same side and away from the face used, in meiosis, for pairing (early first meiotic prophase), (c) where the lateral loops organised by two visibly separate sister chromatids are symmetrically disposed on either side of the chromosome and project away from each other (mitotic prophase and late first meiotic prophase), (d) where the organisation is as in (c) but chromatid axes are intimately fused and form a visibly single strand (female amphibian diffuse diplotene).