macronucleus

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Related to Meganuclei: macronucleus, macronuclear, endomixis, macronuclei

mac·ro·nu·cle·us

(mak'rō-nū'klē-ŭs),
1. A nucleus that occupies a relatively large portion of the cell, or the larger nucleus where two or more are present in a cell.
See also: micronucleus (2). Synonym(s): meganucleus
2. The larger of the two nuclei in ciliates, which governs vegetative metabolic functions and not reproduction.
See also: micronucleus (2). Synonym(s): somatic nucleus, trophic nucleus, trophonucleus

macronucleus

/mac·ro·nu·cle·us/ (-noo´kle-us) the larger of two types of nuclei when more than one is present in a cell.

macronucleus

(măk′rō-no͞o′klē-əs, -nyo͞o′-)
n. pl. macronu·clei (-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.

macronucleus

[-no̅o̅′klē·əs]
Etymology: Gk, makros + L, nucleus, nut
1 a large nucleus that occupies a relatively large portion of the cell.
2 (in protozoa) the larger of two nuclei in each cell, governing cell metabolism and growth as opposed to the micronucleus, which functions in sexual reproduction.

mac·ro·nu·cle·us

(mak'rō-nū'klē-ŭs)
1. A nucleus that occupies a relatively large portion of the cell, or the larger nucleus where two or more are present in a cell.
2. The larger of the two nuclei in ciliates, which governs vegetative metabolic functions and not reproduction.
See also: micronucleus (2)

macronucleus

or

meganucleus

the larger of two nuclei found in some PROTOZOANS, that is concerned with cell division (see MICRONUCLEUS). It disappears during CONJUGATION and is afterwards reformed from material of micronuclear origin (from the zygote nucleus). It appears to have mainly vegetative functions.

macronucleus

the larger nucleus when there are two in the cell.