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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 ?
All species of ciliates harbor two different kinds of nuclei; micronucleus that is required for sexual reproduction and other one is transcriptionally active macronucleus (Baroin-Tourancheau et al.
Unidentified ciliates were recorded in gills, characterized by a big macronucleus and several micronuclei, with dense ciliature (Fig.
The macronucleus is spherical or occasionally elipsoidal, lies on the dorsal side and is located near the middle of the cell.
The micronucleus functions in mitosis and meiosis, whereas the macronucleus maintains routine cell function.
It has macronucleus at the posterior part of the body.
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).
Ciliates possess two or more dimorphic nuclei: an active somatic macronucleus and a transcriptionally inert germline micronucleus.
Interstitial telomeres are hotspots for illegitimate recombination with DNA molecules injected into the macronucleus of Paramecium primaurelia.
Unfortunately for our purposes, the experiments were typically without large-population controls, and even mass [TABULAR DATA FOR TABLE 1 OMITTED] cultures of some ciliates are known to degrade without some way of reconstituting the macronucleus (Takagi and Yoshida 1980).