Macronucleus

Definition

A macronucleus is a type of nucleus in certain unicellular eukaryotes, particularly ciliates, responsible for the regulation of non-reproductive cell functions. It controls everyday metabolic and developmental processes.

5 Must Know Facts For Your Next Test

1. The macronucleus is polyploid, containing multiple copies of the genome.
2. It arises from the micronucleus through a process called DNA amplification.
3. Macronuclei are essential for gene expression and cellular function in ciliates.
4. They do not participate directly in sexual reproduction; that role is reserved for the micronucleus.
5. Macronuclei are often larger than micronuclei due to their extensive genomic content.

Related terms

Micronucleus: A smaller nucleus involved in reproductive processes and genetic recombination.

Ciliate: A group of protozoans characterized by having cilia used for movement and feeding.

Polyploidy: The condition of having more than two complete sets of chromosomes.