MEGANUCLEUS (also called Macronucleus), in Infusoria (q.v.), the large nucleus which undergoes direct (amitotic) division in fission, and is lost during conjugation, to be replaced by a nucleus, the result of the karyogamy of the micronuclei.
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MEGANUCLEUS (also called Macronucleus), in Infusoria (q.v.), the large nucleus which undergoes direct (amitotic) division in fission, and is lost during conjugation, to be replaced by a nucleus, the result of the karyogamy of the micronuclei.