[mak-roh-noo-klee-uh s, -nyoo-]
- the larger of the two types of nuclei occurring in ciliate protozoans, having a multiple set of chromosomes and functioning in cell metabolism and protein synthesis.
Origin of macronucleus
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for macronucleus
The macronucleus is spherical and has one micronucleus attached.
The macronucleus is spherical, elongate, band-formed or horseshoe-shaped.
Macronucleus central, globular to elongate, sometimes double.
The macronucleus is long and band-formed or horseshoe shape.
The macronucleus is spherical and usually central in position.
- the larger of the two nuclei in ciliated protozoansCompare micronucleus
- The larger of two nuclei present in ciliate protozoans, which controls the nonreproductive functions of the cell.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.