Division of Euglypha acantophora
The next photomicrographs show the division of a specimen of Euglypha acanthophora. Both cells were found when the new shell was already build. The left shell is the old shell, the so-called mothercell (m) and the new shell is called the daughter (d). My observation started when the nucleus in the mother cell was already dividing.
The process of the division of the nucleus is called mitose. It starts with the stretching of the nucleus, taking the shape of a spindle. This state is termed prophase, where the chromosomes become visible as longitudinal structures. On the photomicrograph above the chromosomes are arranged in two halves, the chromatids, forming a gap, the equatorial plane. This state is the metaphase. Both chromatids are clearly recognizable
Both chromatids stretch in opposite directions to form the two daughter nuclei. The phase of separation is termed anaphase, the formation of the daughter nuclei telophase.
One of the nuclei (n2) moves through the apertures into the daughter shell.
The daughter nucleus (n2) reaches here position at the back. Later the threadlike structures will disappear. The process from the first photomicrograph till here lasted less than 15 minutes.
During and after the division of the nucleus, the cytoplasm moves through both shells in a turbulent way.
Ten minutes after both specimens separated, one of the cells started with feeding on a filamentous algae.