macronucleus

There are three different sets of self-duplicating nuclei, with the DNA in each set serving different purposes: a large macronucleus, governing the events in regeneration after injury, a set of eight or more micronuclei containing the parts of the genome needed for reproduction, and great numbers of tiny nuclei from which the cilia arise.

The clear spot to the right is the macronucleus, and the blobs are probably storage granules of some sort.

In the centre lies a sizeable macronucleus, which stores the chromatin used for making the various genome products.

The details of ciliate sex, and the behavior of the micronucleus and the macronucleus, differ slightly from one species to the next; my description is taken from the aforementioned Margulis and Schwartz, and also from Jönsson, F., Postberg, J. and Lipps, H. J. 2009.

The macronucleus is made from the micronucleus, but it is not at all the same in content.