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Related to macronucleus: oral groove


 (măk′rō-no͞o′klē-əs, -nyo͞o′-)
n. pl. mac·ro·nu·cle·i (-klē-ī′)
The larger of two nuclei present in ciliate protozoans, which controls nonreproductive functions of the cell, such as metabolism.

mac′ro·nu′cle·ar adj.


n, pl -clei (-klɪˌaɪ)
(Microbiology) the larger of the two nuclei in ciliated protozoans. Compare micronucleus


(ˌmæk roʊˈnu kli əs, -ˈnyu-)

the larger of the two types of nuclei in ciliate protozoans, functioning in cell metabolism. Compare micronucleus.
mac`ro•nu′cle•ar, adj.
References in periodicals archive ?
It gives rise to a workaday version of itself, a macronucleus, with just the animal's 27,000 or so genes and not the 95 percent of DNA that scientists typically call junk because it doesn't encode any proteins.
23] Finally, ciliocytophthoria are anucleate (Figures 1 through 3), whereas B coli have a macronucleus that is typically indented or kidney shaped (Figure 4).