Cell Structure.

http://en.wikipedia.org/wiki/Ciliate

Nuclei

Unlike most other eukaryotes, ciliates have two different sorts of nuclei: a small,diploid micronucleus (reproduction), and a large, polyploid macronucleus (general cell regulation). The latter is generated from the micronucleus by amplification of the genome and heavy editing. The micronucleus serves as the germ line nucleus, but does not express its genes. The macronucleus provides the nuclear RNA for vegetative growth.