Special types of chromosomes

The preceding section in this section dealing with chromosomes in eukaryotes was devoted to structure and function of chromosomes as observed in mitotic or meiotic cells in plants and animals. In certain organisms there are special tissues where these chromosomes take up a special structure. Lampbrush chromosomes of the vertebrate oocyte and giant chromosomes of salivary gland cells of dipterans are such special types of chromosomes. Due to special significance of these chromosomes, a relatively detailed account of these two types of chromosomes will be presented.