Macronucleus

The macronucleus ( macronucleus ) is the name given to the large nucleus of the eyelash animal (for example the paramecium ). It lies in these single cells as a larger, usually bean-shaped, polyploid structure next to the much smaller micronucleus or next to several micronuclei. During the conjugation process , the macronucleus is dissolved, but later re-forms.